Roasted Garlic and Spinach Soup

Name: Roasted Garlic and Spinach Soup
Prep time: 15 min
Cook time: 1 h 9 min
Total time: 1 h 24 min
Yield: 6 servings
Cuisine: American
Ingredients: 2 large heads (120 g) whole garlic heads, papery skin left on, top ¼ inch (6 mm) sliced off to expose the cloves; 1 tablespoon (15 ml) olive oil, for drizzling over the garlic; 2 tablespoons (30 ml) olive oil; 1 large (about 9 oz) (250 g) yellow onion, peeled and chopped into ½-inch (1 cm) pieces; 1 pound (450 g) Yukon Gold potatoes, peeled and cut into ¾-inch (2 cm) cubes; 4 cups (960 ml) vegetable broth; 1 cup (240 ml) water; 1 teaspoon (6 g) kosher salt, plus more to taste; ¼ teaspoon (½ g) black pepper, freshly ground; 10 ounces (280 g) fresh baby spinach, rinsed and drained (about 10 loosely packed cups); 2 tablespoons (30 ml) lemon juice, freshly squeezed, from about 1 lemon, plus more to taste; 1 teaspoon (2 g) lemon zest, finely grated, for garnish (optional); 2 tablespoons (30 ml) extra-virgin olive oil, for drizzling over the bowls (optional)

From the MyKitchenBank Kitchen

Two whole heads of garlic roast until sweet and spreadable, then melt into a silky potato-and-onion base. Fresh spinach goes in for just a few minutes so the soup stays bright green, and a squeeze of lemon lifts it all at the end.

Prep: 15 min
Cook: 1 hr 9 min
Total: 1 hr 24 min
Makes: About 7 cups (1.7 L), serving 6 as a starter or 4 as a light main

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Ingredients

6 servings

For the roasted garlic
2 large heads (120 g) whole garlic heads, papery skin left on, top ¼ inch (6 mm) sliced off to expose the cloves
1 tablespoon (15 ml) olive oil, for drizzling over the garlic
For the soup
2 tablespoons (30 ml) olive oil
1 large (about 9 oz) (250 g) yellow onion, peeled and chopped into ½-inch (1 cm) pieces
1 pound (450 g) Yukon Gold potatoes, peeled and cut into ¾-inch (2 cm) cubes
4 cups (960 ml) vegetable broth
1 cup (240 ml) water
1 teaspoon (6 g) kosher salt, plus more to taste
¼ teaspoon (0.5 g) black pepper, freshly ground
10 ounces (280 g) fresh baby spinach, rinsed and drained (about 10 loosely packed cups)
To finish
2 tablespoons (30 ml) lemon juice, freshly squeezed, from about 1 lemon, plus more to taste
1 teaspoon (2 g) lemon zest, finely grated, for garnish (optional)
2 tablespoons (30 ml) extra-virgin olive oil, for drizzling over the bowls (optional)

Equipment (6)

Small rimmed baking sheet or baking dish
Aluminum foil
4- to 5-quart (3.8-4.7 L) Dutch oven or heavy soup pot
Immersion blender or countertop blender (6-cup / 1.4 L capacity or larger)
Chef's knife and cutting board
Wooden spoon and ladle

Steps

Before you start

Read the timing first: the garlic roasts for 40 minutes, and you chop the vegetables while it roasts.
Use an immersion blender, or a countertop blender with a vented lid, so hot soup can be blended safely.
Choose a vegetable broth you enjoy drinking, since it is most of the flavor. Low-sodium broth lets you control the salt.
Rinse the spinach and shake off excess water. Baby spinach needs no stem trimming.

1
Prep the garlicOven 400°F / 205°C
- Position a rack in the center of the oven and heat to 400°F (200°C).
- Set the garlic heads cut-side up on a sheet of foil about 10 inches (25 cm) square.
- Drizzle 1 tablespoon (15 ml) olive oil over the exposed cloves, letting it sink in, then wrap the foil snugly around the garlic to form a sealed packet.
- Set the packet on a small baking sheet.
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Ready when: Oven is fully preheated and the garlic is sealed in foil.
Tip: Seal the foil tightly so the garlic steams in its own moisture and turns soft rather than dry.
2
Roast garlic, chop vegetablesOven 400°F / 205°C
- Roast the garlic at 400°F (200°C) for 40 minutes.
- While it roasts, chop the onion into ½-inch (1 cm) pieces and peel and cube the potatoes into ¾-inch (2 cm) cubes.
- Keep the potatoes in a bowl of cold water if you are not cooking them right away, then drain well before using.
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Ready when: Cloves are deep golden, and a knife tip slides into them with no resistance. They should smell sweet and nutty, not sharp.
Tip: If the cloves still feel firm, re-wrap and roast another 5-10 minutes.
3
Soften the onion
- Heat 2 tablespoons (30 ml) olive oil in the Dutch oven over medium heat until it shimmers.
- Add the onion and 1 teaspoon kosher salt.
- Cook, stirring every minute or so, for 8 minutes until the onion is soft and translucent with no browning.
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Ready when: Onion is soft, translucent and pale gold, with no dark brown edges.
Tip: Lower the heat to medium-low if the onion starts to brown, since browning would dull the soup's green color and sweet flavor.
4
Simmer the potatoes
- Add the potatoes, broth, water and pepper to the pot.
- Raise the heat to high and bring to a boil, then reduce to medium-low so the soup simmers gently.
- Partially cover and cook for 15 minutes.
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Ready when: A potato cube falls apart easily when pressed against the side of the pot with a spoon.
Tip: Take the garlic out of the oven once it is done and let it cool, still wrapped, while the potatoes simmer.
5
Add garlic and spinach
- Carefully open the foil packet (steam will escape).
- Squeeze the soft roasted cloves from their skins into the pot; discard the skins.
- Stir to break up the garlic.
- Add the spinach in 3 or 4 handfuls, stirring until each addition wilts.
- Simmer for 2 to 3 minutes once all the spinach is in.
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Ready when: Spinach is completely wilted and still bright green.
Tip: Do not cook the spinach longer than 3 minutes, or the soup turns an olive-drab color.
6
Blend until smooth
- Remove the pot from the heat.
- With an immersion blender, blend directly in the pot for 1 to 2 minutes until completely smooth and velvety.
- Or cool the soup for 5 minutes and blend in 2 or 3 batches in a countertop blender, filling it no more than half full, with the lid vented and covered with a folded towel.
- Return it to the pot.
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Ready when: Soup is uniformly green and silky, with no flecks of spinach or lumps of potato.
Tip: Hot liquid expands in a sealed blender and can blow the lid off. Always vent the lid and hold it down with a towel.
7
Season with lemon
- Stir in 2 tablespoons (30 ml) lemon juice.
- Taste and add more salt, a pinch at a time, or more lemon juice, a teaspoon at a time, until the flavor tastes bright and balanced.
- If the soup is too thick, thin it with 2 to 4 tablespoons of hot water.
- Re-warm over low heat for 1 to 2 minutes if needed.
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Ready when: The soup tastes savory, sweet from the garlic, and lightly tangy, and it coats the back of a spoon.
Tip: Add lemon at the end; cooking it longer dulls both the flavor and the green color.
8
Serve
- Ladle the hot soup into 6 warm bowls.
- Drizzle each with about 1 teaspoon extra-virgin olive oil and sprinkle with a little lemon zest, if using.
- Serve right away.
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Ready when: Soup is steaming hot and vividly green.

Good to know

Tips

For a richer, creamier soup, stir in ¼ cup (60 ml) heavy cream or full-fat coconut milk after blending.
Blend longer than you think you need to; a full 2 minutes gives the smoothest texture.
Season in stages: the potatoes absorb salt, so tasting after blending gives the truest result.
Top with crunchy toasted bread cubes or toasted pumpkin seeds for contrast.

Make ahead

Make the soup through step 6 up to 3 days ahead and refrigerate. Cool it quickly, uncovered, for 30 minutes, then chill in airtight containers. Reheat gently and add the lemon juice just before serving for the brightest flavor. The garlic can be roasted up to 3 days ahead and refrigerated in its foil.

Storage & reheating

Room temperature: up to 2 hours. Refrigerator: up to 4 days in an airtight container. Freezer: up to 3 months in freezer-safe containers, leaving 1 inch (2.5 cm) of headspace; thaw overnight in the fridge. Reheat over medium-low heat, stirring often, until steaming; add a splash of water or broth if it has thickened.

Substitutions

fresh baby spinach → Frozen chopped spinach, 10 oz (280 g), thawed and squeezed dry. Add with the garlic and simmer 3 minutes; the color will be a bit darker.
Yukon Gold potatoes → Russet potatoes, same weight. Russets make a slightly thicker, fluffier soup; Yukon Golds are creamier.
olive oil → Unsalted butter, 2 tablespoons (28 g). Gives a richer taste; the soup is then no longer vegan.
lemon juice → White wine vinegar, 1 tablespoon (15 ml). Add a teaspoon at a time and taste, as it is sharper than lemon.