12 medium ripe but firm not refrigerated tomatoes
1 cup olive oil
3 cups chopped onions
1 fennel bulb, trimmed and finely chopped
1 tablespoon fennel seeds, preferably freshly ground or crushed in a mortar
1 cup medium-grain rice, such as Arborio
1 cup chopped fresh flat-leaf parsley
1 cup chopped fresh dill
1/2 cup chopped fresh mint
11/2 teaspoons salt, plus more to taste
Freshly ground black pepper
1 medium potato, scrubbed, halved crosswise and each half quartered
Preheat the oven to 375°F.
Cut off the top 1/2 inch of each tomato; set aside the tops. Using a grapefruit spoon, very carefully remove as much pulp as possible from each tomato, without piercing the skin.
Chop the pulp. Measure out 21/2 cups; freeze the rest for another use, if desired.
In a large skillet, heat 2/3 cup of the oil and sauté the onions and fennel bulb over medium heat for 5 minutes, or until soft.
Add the fennel seeds and rice and sauté, stirring, for 2 to 3 minutes.
Add 2 cups of the tomato pulp, reduce the heat to low and cook, stirring, for 3 minutes more.
Stir in the parsley, dill and mint and cook for 2 minutes more.
Remove from the heat and add the salt and plenty of pepper.
Stuff the tomatoes with the rice mixture, leaving a little room for the stuffing to expand, and cover with the tomato tops.
Place the tomatoes in a 13-x-9-inch baking dish and arrange the potato pieces in the gaps between the tomatoes.
Pour the remaining 1/2 cup tomato pulp over everything and drizzle the tomatoes with the remaining 1/3 cup oil.
Sprinkle with salt and pepper to taste.
Bake for 1 hour, or until the rice is tender (lift the cover of a tomato and check).
Turn off the oven and let stand in the oven for 10 minutes, then let cool to room temperature.
Serve 1 or 2 tomatoes and a couple of potato pieces on each plate.