The trick with potata bravas is to cook the sauce ahead of time and then allow it to cool, which will thicken it and intensify the flavours. Chop and fry a large onion, two garlic cloves and a red chilli in a frying pan. Add a can of chopped tomatoes and (if you like it spicy) Tobasco then season to taste. Once cooked through, turn off the heat and set aside.
Take a bag of new potatoes and cut each one in half. Place in a casserole dish, cover with a little oil and roast in the oven.
On this occasion, I’m using two whole sea bass which I’ve gutted (if you’ve never done this before, just Google for instructions – it’s a little messy but fairly straightforward). If you want to eat the skin, you will also need to de-scale it, but as I plan to flake the fish, I’m leaving it as it is. Place each fish on a sheet of foil, sprinkle over lemon juice and wrap it up.
Empty fresh spinach into a smaller casserole dish and add a knob of butter. Stack the wrapped fish and spinach in the oven. Remove the potatoes, cover with the chilled bravas sauce and return to the shelf. Cook everything for a further twenty minutes and serve immediately for a great tapas-style supper.