Oven-Finished Frittata with Red Pepper and Spinach
Inspired by techniques from NYT Cooking and America's Test Kitchen.
A hearty Italian-style frittata built from softened onion and red pepper, wilted spinach and a cheese-flecked egg mixture, started gently on the hob and finished under a hot grill until puffed and fully set. It makes a satisfying brunch, lunch or light supper, served warm in wedges.
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Method
- 1
Whisk the eggs. Whisk the eggs, milk, salt and pepper together in the bowl, then stir in the grated cheese, until the mixture is evenly yellow, about 30 seconds. The milk loosens the eggs slightly so the finished frittata stays tender rather than dense, while the cheese seasons it from within.
- 2
Soften onion and pepper. Heat the oil in the pan over medium heat and cook the onion and red pepper for 8-10 minutes, stirring occasionally, until soft and lightly golden. Slow, steady cooking breaks down the vegetables' structure and sweetens them, so neither stays crunchy nor turns bitter from scorching.
- 3
Wilt the spinach. Add the garlic and cook for 30 seconds until fragrant, then stir in the spinach and cook for 1-2 minutes until wilted and any liquid released has evaporated. Driving off this liquid now stops the frittata turning watery once the egg goes in.
- 4
Set the base. Heat the grill (broiler) to high with a shelf about 15cm below it. Turn the heat under the pan down to medium-low, pour in the egg mixture and stir gently for 30 seconds so the filling is evenly spread, then leave undisturbed for 6-8 minutes, lifting the edge once or twice to let liquid egg run underneath. The base and edges should be set while the top stays wet, since finishing gently on the hob first keeps the frittata from catching before the grill takes over.
- 5
Finish under the grill. Carefully transfer the pan to the grill — use oven gloves, as the handle is now very hot — and grill for 3-5 minutes until puffed, lightly golden and set right through. A knife pushed into the centre should come out completely clean with no liquid egg, and the centre should reach 71°C; strong, even heat from above is what sets the top fully without drying out the base.
- 6
Rest and serve. Let the frittata rest for 5 minutes, then loosen it with the spatula and slide it onto the plate before cutting into wedges. Resting allows the egg to firm up fully and makes it much easier to cut into neat slices. Serve hot or warm.

Cat tip
Dry the pan vegetables well before adding the eggs — any leftover liquid will make the frittata watery instead of firm.
More from the cat
- A common mistake is grilling at too low a heat or too far from the element; keep the shelf close and the grill on high so the top sets and colours before the base dries out.
- Cook the onion and pepper slowly over medium heat; well-softened vegetables taste sweeter and won't stay crunchy in the egg.
- Let the frittata rest for the full 5 minutes before cutting, so it holds together in neat wedges rather than collapsing.
Storage
Refrigerate leftovers within 1 hour, use within 2 days, and either eat cold or reheat until piping hot all the way through (74°C). Cool leftovers in a shallow container and refrigerate within 2 hours (within 1 hour on a day above 32°C).
Equipment
- 25 cm ovenproof non-stick frying pan
- large bowl
- whisk or fork
- heatproof silicone spatula
- oven gloves
- instant-read thermometer
- chopping board and knife
- plate or board for serving
Nutrition per serving (estimated values)
| Per serving | Amount |
|---|---|
| Energy | 268 kcal |
| Protein | 16.7 g |
| Carbohydrate | 8.8 g |
| of which sugars | 4.4 g |
| of which free sugars | 0 g |
| Fat | 18.4 g |
| of which saturates | 5.3 g |
| Fibre | 2.2 g |
| Salt | 1.4 g |
Protein per 100 kcal
6.2 g High Protein needs ≥ 10 g
Calculated from USDA FoodData Central ingredient values
