Cut the peppers in half lengthwise, clean and wash them. Blanch frozen peas in boiling salted water for about 2 minutes, drain and rinse. Put the couscous in a bowl and pour 350 ml of boiling water over it. Mix with 1 tsp. salt, 1 tbsp. olive oil and pesto and leave to stand for about 5 minutes
Mix the peas into the couscous. Season to taste with salt and pepper. Fill the couscous into the peppers. Crumble the feta cheese and sprinkle over the couscous. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 15 minutes
In the meantime, wash the basil and shake dry. Put a few leaves aside for garnishing. Finely chop the remaining leaves. Peel onion and chop finely. Heat 1 tablespoon of olive oil in a saucepan. Fry the onion for about 2 minutes at medium heat until transparent. Add tomato paste and steam briefly. Deglaze with chunky tomatoes. Let the sauce simmer for about 5 minutes, stirring occasionally. Season to taste with salt, pepper and chopped basil
Arrange the stuffed peppers on a plate. Garnish with basil leaves. Add tomato sauce