Cut a hat in the top of each tomato, on the side of the peduncle. Gently scoop out the pulp.
Prepare a stuffing with half of the chopped onions and half of the grease, brown the minced meat in the pan, mixing it to obtain a homogeneous stuffing. Season.
Fill the tomatoes with this stuffing. Arrange a slice of bruccio on top. Put the hats back in place. Drizzle with olive oil. Season and cook for 5/6 minutes in the oven preheated to 180°C (th. 6). The tomatoes are done when they show a slightly wrinkled skin.
Prepare the rest of the onions, leaving them with 2 cm of stalk, cut them in half, brown them in a pan with the rest of the grease. Season.
Make a vinaigrette with the vinegar and olive oil, season the lamb’s lettuce, arrange it in the middle of the plates with the stuffed tomatoes and the grease, drizzle with the reduced and lukewarm chicken jus.