Cuore di vitello alla trasteverina

• juice of 1 lemon
• 6 tablespoons (90 ml) intensely fruity extra-virgin olive oil

Put the lemon juice in a bowl and add the oil and a generous grinding of pepper. Trim the heart, then cut into pieces weighing about 1¾ ounces (50 g) each. Add to the marinade, stir to coat, and let