Preheat the oven to Gas 5, 190°C, fan 170°C.
Drain the peppers and use a little of the oil to grease four ramekin dishes. Set the remaining oil aside. Put the spinach into a large pan and season with salt and freshly ground black pepper. Cook, covered, for 2-3 minutes until wilted. Drain, squeeze out excess water and chop finely.
Heat 1tbsp of the reserved oil from the peppers in a pan. Add the spinach and cook for 1min, stirring. Add the chopped peppers and season. Divide the mixture among the four ramekins, making a hollow in the centre of each.
Crack an egg into each hollow and grate a little fresh nutmeg on top. Stand the ramekins in a roasting tin and pour in enough boiling water to come halfway up the sides. Cover the tin loosely with foil and bake the filled ramekins in the oven for 12-15 minutes until the eggs are just set. Serve with toasted ciabatta.