Wrap some lard around each fillet, tie them with some kitchen string and place some rosemary under the string. Peel and slice the garlic.
Cut the Gorgonzola into small pieces. Melt the butter and two tablespoons of oil in a frying pan, let the garlic get golden brown, add the fillets and cook them on a high flame for 2 minutes per side.
Add the salt, pepper and small pieces of Gorgonzola on the fillets. Place them in the pre-heated oven for 3 minutes and serve them immediately.
The fillets can be served with some grilled tomatoes.