Egg Muffin Cups with Spinach and Cheese

Name: Egg Muffin Cups with Spinach and Cheese
Prep time: 21 min
Cook time: 28 min
Total time: 49 min
Yield: 6 servings
Cuisine: American
Ingredients: 1 tbsp (15 ml) olive oil; 1 medium (about 6 oz) (170 g) red bell pepper, seeded and cut into ¼-inch (6 mm) dice; 5 oz (140 g) fresh baby spinach, roughly chopped; 3 whole (45 g) scallions, trimmed and thinly sliced (white and green parts); 10 whole (500 g) large eggs, at room temperature if possible; ½ cup (120 ml) whole milk; ¾ tsp (4 g) kosher salt; ¼ tsp (½ g) black pepper, freshly ground; ½ tsp (1½ g) garlic powder; 4 oz (about 1 cup) (113 g) sharp cheddar cheese, coarsely shredded; 1 tbsp (14 g) nonstick cooking spray or softened butter, for greasing the tin

From the MyKitchenBank Kitchen

Fluffy, protein-rich baked egg cups packed with sautéed spinach, sweet bell pepper, scallions and sharp cheddar. They release cleanly from the tin, reheat well, and make a grab-and-go breakfast for the whole week.

Prep: 21 min
Cook: 28 min
Wait: 10 min
Total: 59 min
Makes: 12 egg muffin cups (2 per serving)

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Ingredients

6 servings

1 tbsp (15 ml) olive oil
1 medium (about 6 oz) (170 g) red bell pepper, seeded and cut into ¼-inch (6 mm) dice
5 oz (140 g) fresh baby spinach, roughly chopped
3 whole (45 g) scallions, trimmed and thinly sliced (white and green parts)
10 whole (500 g) large eggs, at room temperature if possible
½ cup (120 ml) whole milk
¾ tsp (4 g) kosher salt
¼ tsp (0.5 g) black pepper, freshly ground
½ tsp (1.5 g) garlic powder
4 oz (about 1 cup) (113 g) sharp cheddar cheese, coarsely shredded
1 tbsp (14 g) nonstick cooking spray or softened butter, for greasing the tin

Equipment (10)

Standard 12-cup muffin tin (about ½ cup / 120 ml capacity per cup)
Large nonstick skillet, 10–12 inch (25–30 cm)
Large mixing bowl or 8-cup (2 L) liquid measuring jug with pouring spout
Whisk
Chef's knife and cutting board
Box grater (if shredding cheese)
Instant-read thermometer
Small offset spatula or butter knife for loosening cups
Clean kitchen towel or fine mesh sieve for squeezing spinach
Tablespoon measure or small ladle (¼ cup / 60 ml) for portioning

Steps

Before you start

Position an oven rack in the center and preheat the oven to 350°F (175°C) before you begin.
Shred the cheddar from a block if you can; pre-shredded cheese contains anti-caking starch and melts less smoothly.
Use a standard 12-cup muffin tin (not mini or jumbo), and grease every cup generously, even if the tin is nonstick.
The spinach must be squeezed dry after cooking. Extra water is the main cause of soggy, weepy egg cups.

1
Preheat and grease tinOven 350°F / 175°C
- Position a rack in the center of the oven and preheat to 350°F (175°C).
- Grease all 12 cups of a standard muffin tin thoroughly with cooking spray or softened butter, covering the bottoms, sides and the flat top rim around each cup.
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Ready when: Every cup looks evenly glossy with no dry patches.
Tip: Don't skip the rim: egg that puffs over the edge sticks there and can tear the cups.
2
Prep the vegetables
- Seed the bell pepper and cut it into ¼-inch (6 mm) dice so it cooks through in the short bake.
- Roughly chop the spinach, thinly slice the scallions, and shred the cheddar if it isn't already shredded.
- Keep the cheese and scallions in separate piles for later.
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Ready when: Pepper pieces are uniformly small, about the size of a pea.
Tip: Large pepper chunks release water and leave gaps in the cups, so keep the dice small.
3
Sauté pepper and spinach
- Heat the olive oil in a large nonstick skillet over medium heat until it shimmers.
- Add the diced bell pepper and cook, stirring often, for 3 to 4 minutes until slightly softened but still bright.
- Add the chopped spinach in two handfuls and cook, tossing, for 1 to 2 minutes until fully wilted and the pan looks mostly dry.
- Remove from the heat.
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Ready when: Pepper is just tender when pressed with a spoon; spinach is dark green, wilted and no longer shedding liquid.
4
Cool and squeeze dry
- Spread the cooked vegetables on a plate or tip into a bowl and let them cool for about 5 minutes so they don't start cooking the eggs.
- Then press them in a fine mesh sieve or wrap in a clean kitchen towel and squeeze out as much liquid as you can.
- Stir in the scallions.
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Ready when: Vegetables are only warm to the touch and no liquid drips when pressed.
Tip: Excess moisture is the number one cause of watery egg cups.
5
Whisk the egg mixture
- In a large bowl or jug with a spout, crack the 10 eggs and add the milk, kosher salt, black pepper and garlic powder.
- Whisk vigorously for about 30 seconds until the mixture is completely uniform, pale yellow and slightly frothy with no streaks of white.
- You will have about 2½ cups (570 ml) of egg mixture.
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Ready when: No visible streaks of egg white remain.
Tip: Using a jug with a spout makes pouring into the cups much neater.
6
Fill the cups
- Divide the vegetable mixture evenly among the 12 cups (about 2 heaped tablespoons each), then sprinkle in about two-thirds of the cheddar.
- Stir the egg mixture once more, then pour it evenly over the fillings, about 3 tablespoons (45 ml) per cup, so each cup ends up about three-quarters full.
- Pour a little less into each cup at first and top up so the last cup gets the same as the first.
- Top with the remaining cheese.
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Ready when: All 12 cups are about three-quarters full and the egg mixture is used up.
Tip: Don't fill to the top: the eggs puff up as they bake and will overflow, then sink as they cool.
7
Bake the egg cupsOven 350°F / 175°C
- Bake on the center rack at 350°F (175°C) for 20 to 24 minutes.
- The cups are done when the tops are puffed and set, the centers spring back when lightly pressed, and a knife inserted in the center comes out clean.
- An instant-read thermometer in the center of a cup should read 160°F (71°C).
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Ready when: Tops are puffed, lightly golden at the edges, no wobble in the center, and the interior reads 160°F (71°C).
Tip: Overbaking makes the cups rubbery and watery; start checking at 20 minutes.
8
Rest and release
- Let the tin rest on a wire rack for 5 minutes; the puffed cups will settle slightly.
- Run a small offset spatula or butter knife around the edge of each cup, then lift them out.
- Serve warm.
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Ready when: Cups pull away slightly from the sides and lift out intact.
Tip: Releasing too soon makes them fall apart; waiting too long lets them stick as they cool.

Good to know

Tips

Squeeze the cooked spinach very dry; it is the key to firm, fluffy cups rather than watery ones.
Grease generously, including the rim, or use silicone muffin liners for easier release.
Keep the added milk to ½ cup. More liquid makes the cups spongy and prone to weeping.
Add cooked crumbled bacon or diced ham (about ½ cup / 75 g) in place of some vegetables for a heartier version.

Make ahead

Bake the cups up to 4 days ahead, cool completely, and refrigerate in an airtight container. You can also prep the cooked, squeezed vegetables and shredded cheese up to 1 day ahead and keep them chilled; whisk the eggs just before baking.

Storage & reheating

Room temperature: up to 2 hours after baking. Refrigerator: up to 4 days in an airtight container, with paper towel between layers. Freezer: up to 2 months; freeze on a tray until firm, then bag. Reheat from the fridge in the microwave for 30 to 45 seconds, or from frozen for 60 to 90 seconds (wrapped in a damp paper towel), until steaming hot at 165°F (74°C). Or reheat in a 350°F (175°C) oven for 10 to 15 minutes.

Substitutions

sharp cheddar cheese → Gruyère, Monterey Jack or feta. Use the same weight. Feta is saltier, so reduce the added salt to ½ tsp.
fresh baby spinach → 10 oz (280 g) frozen chopped spinach. Thaw fully and squeeze very dry in a towel; skip the sautéing and add directly to the cooked pepper off the heat.
whole milk → Half-and-half or unsweetened plain oat milk. Half-and-half gives richer, creamier cups; oat milk works well for dairy-light versions.
red bell pepper → Diced mushrooms or sun-dried tomatoes. Cook mushrooms until their liquid evaporates, about 5 minutes; use ¼ cup (40 g) chopped oil-packed sun-dried tomatoes, drained.