Preheat the oven to 400F.
Toss the tomatoes and EVOO with salt and pepper in a medium bowl until well coated. Add tomatoes to a 2-3 qt. baking dish. Smush the 'nduja between your fingers and scatter the pieces around the baking dish.
Bake for 30 minutes, until the tomatoes have started to burst and the feta is soft and slightly golden. Increase the heat to 450F, and continue to cook until everything is caramalized, 10 to 15 minutes more.
While the tomatoes bake, cook the pasta according to the package instructions. Just before draining, grab a coffee cup and use it to reserve 1/2 cup of pasta water.
After 40-45 minutes, remove the baking dish from the oven and add in the chopped garlic. Stir and smush the tomatoes and feta around until a sauce begins to form. Add in the pasta, half of the chopped basil, and a splash of pasta water. Continue to stir until the sauce coats the noodles. Add more water if the sauce becomes too thick.
Dish up the pasta onto plates, top with remaining chopped basil and flaky salt.
