Spread the flour on a large plate and season well.
Dust the brill in the flour, shaking off the excess.
Heat 25g butter in a large frying pan or flat grill plate and cook the brill for 2-3 mins each side, carefully turning it over with a fish slice to prevent it breaking. Check it’s cooked all the way through.
Transfer the brill to a serving plate and keep warm in a low oven.
Add the remaining butter to the pan and cook over a medium heat until golden brown in colour with a nutty aroma.
Add the capers, lemon juice, garlic, parsley and season then cook for 2 mins.
To serve, pour the brown butter and capers over the brill and serve with green salad or boiled potatoes.