Puttanesca Stew

Ingredients

• 2 tablespoons olive oil
• 2 medium white onion
• 2 yellow peppers
• pinch of flaky sea salt
• 4 cloves garlic
• 1 tablespoon tomato purée
• 1 teaspoon dried red chilli flakes
• 3 teaspoons baby capers (nonpareilles)
• 50 g pitted black olives
• 17 oz canned butter beans
• 2 x 14 oz tins chopped tomatoes
• 13.5 fl oz vegetable stock
• 1 lemon
• 2 teaspoons maple syrup
• small handful of basil
• 1 pinch of freshly ground black pepper