To make the sauce, fry the mushrooms lightly in the butter in a small saucepan for 5-10 minutes or until tender. Add the cream and simmer over a gentle heat for 2-3 minutes, or until slightly thickened. Season with salt, pepper and grated nutmeg and set aside.
Cut tofu in half then slice each half horizontally so that you get four thin slices from each-eight in all. Sandwich these pairs, using garlic paste as "glue" to make four fillets. Brush the tofu fillets all over with olive oil and cook them on a hot griddle, so they cook through and get marked with black grid lines, turning them to cook on both sides. Alternatively, you can shallow-fry them in olive oil until crisp and golden.
When the fillets are done, quickly reheat the sauce and serve with them.