Prepare the Porcini Mushrooms: Place the dried porcini mushrooms in a small bowl and cover with 150ml of just-boiled water. Cover and soak for 5 minutes. Once softened, strain the soaking liquid through a fine sieve and set it aside, topping up with extra water to make 200ml if needed. Crumble in the bouillon cube and stir to dissolve. Finely chop the soaked mushrooms.
Heat your oven to 180°C (350°F).
Prepare the Tomatoes: Slice the tops off the tomatoes and set them aside. Using a teaspoon, carefully scoop out the pulp and seeds. Blend the pulp until smooth and set it aside. If you don’t have 200ml of pulp, blend in an extra tomato to make up the volume.
Make the Filling: Season the inside of each tomato shell with a little salt. Arrange the hollowed-out tomato shells snugly upright in a baking dish or roasting tin.
Heat a little olive oil in a large frying pan over medium heat. Sauté the diced onion until soft. Add the pork mince and cook until browned. Stir in the oregano, garlic, and a pinch of chilli flakes (if using), and cook for another minute.
Add the rice, chopped porcini mushrooms, and the reserved porcini mushroom stock. Bring to a boil, then reduce the heat and simmer. Cover and cook for 10–12 minutes, stirring occasionally, until the rice is almost cooked but still al dente.
Remove the pan from the heat. Stir in the lemon zest, chopped herbs, reserved blended tomato pulp, and grated Parmesan. Gently combine, then taste and season with salt and pepper as needed.
Assemble and Roast: Spoon the filling into each tomato shell, being careful not to pack it down—the rice will expand as it finishes cooking. Place the tomato tops back on, drizzle generously with olive oil, and sprinkle with salt.
Cover the dish with foil and bake for 30 minutes. Remove the foil and bake uncovered for another 20 minutes, until the tomatoes are soft and beginning to caramelise on top.
To Serve: Grate a fresh tomato and discard the skin. Stir in a splash of olive oil, a squeeze of lemon juice, and a pinch of sea salt. Spoon this fresh tomato salsa into shallow bowls and top with one or two stuffed tomatoes. Finish with a drizzle of olive oil and a few fresh basil leaves.