On a cooktop, in a large enamel cast iron skillet or similar, place the pasta nests or pasta in the center.
Arrange halved cherry tomatoes, sliced onion, garlic, and basil around the pasta.
Top the pasta with the fire-roasted tomatoes, tomato paste, season with Kosher salt, black pepper, red pepper flakes (optional), and drizzle the extra virgin olive oil over everything.
Pour the broth over the pasta, cover, and bring it to a low boil. Cook for 1-12 minutes, stirring occasionally with a wooden spoon to prevent the pasta from sticking.
When the pasta is al dente and all the other ingredients have cooked and softened, turn off the heat and slowly add the heavy cream to the mixture. Stir until well combined and warmed through. The sauce should be slightly thick.
If needed, reduce the heat to low and cook uncovered until the sauce reaches your desired consistency.Cook uncovered for 2–3 minutes if the sauce needs to thicken more. Garnish with grated cheese, more red pepper flakes if desired, and serve!