vegetarianPreheat the oven
Set the oven to 400� F (200� C) so it is fully hot by the time the vegetables are ready to roast. Place a large sheet pan on the counter and, if you like easier cleanup, line it with parchment.
Wash the produce
Rinse the Cherry Tomatoes and the Basil Leaves under cool water, then dry them well. Keeping the tomatoes fairly dry helps them roast instead of getting watery on the pan.
Prep the aromatics
Peel the Shallot and cut it into wedges or thick slices so it roasts evenly without burning. Peel the Garlic cloves as well, leaving them whole if they are small or halving them if they are very large.
Season the vegetables
Spread the tomatoes, shallot, and garlic on the sheet pan. Drizzle with Olive Oil, then sprinkle over the Italian Seasoning, Red Pepper Flakes, Salt, and Black Pepper. Toss everything well so the vegetables are evenly coated, then spread them into a single layer with as much cut side contact with the pan as possible.
Roast until blistered
Roast the seasoned vegetables for 45 to 50 minutes, stirring once about halfway through, until the tomatoes have burst, the shallot is very soft, and a few edges are nicely charred. You want deep roasting here because that concentrated flavor is what makes the sauce rich without cream.
Blend the sauce
Carefully transfer the hot roasted tomatoes, shallot, and garlic to a blender. Add the basil and the Vegetable Stock, then blend until the sauce is completely smooth and silky. Taste it; if the tomatoes are especially sharp, blend in a small pinch of Sugar to round out the acidity.
Boil the rigatoni
Bring a large pot of water to a boil and season it generously with more salt so the pasta is flavorful from the inside out. Add the Rigatoni Pasta and cook it until al dente, following the package timing. Just before draining, scoop out about 1 cup of Pasta Water and set it aside.
Brown butter and simmer
While the pasta cooks, melt the Unsalted Butter in a large pan over medium-high heat. Cook it, swirling often, until it turns golden brown and smells nutty, then immediately pour in the blended tomato sauce. Let the sauce simmer for 2 to 3 minutes so the flavors come together, then stir in the Parmesan Cheese until melted and smooth.
Drain the pasta
Drain the rigatoni once it is al dente, but do not rinse it. The starch clinging to the pasta helps the sauce grab on and become glossy.
Toss and serve
Add the drained rigatoni to the pan of sauce and toss well so every piece is coated. If the sauce looks too thick, add the reserved pasta water a splash at a time until it becomes creamy and fluid. Taste and adjust with more salt, black pepper, or red pepper flakes if needed. Serve hot, finished with extra Parmesan, more basil leaves, and, if you like, Mozzarella Cheese Balls for a soft, melty garnish.
