1/4 cup freshly grated parmesan cheese + more for serving
4 cloves garlic, peeled
1/2 tsp kosher salt
1/2 tsp fresh ground black pepper
2 tbsp unsalted butter
3 tbsp heavy cream
1/2 tsp red pepper flakes
1 lb linguine or pasta of choice
1/3 cup reserved pasta water
Bring 4 quarts of salted water to a boil, cook pasta to al dente according to package instructions. Reserve 1/3 cup of pasta water and drain pasta.
While pasta is cooking, in a food processor add the basil leaves, garlic cloves, pine nuts, cheese, salt/pepper. Blend on high and slowly add in the olive oil. Open and scrape the sides with a spatula to get any leaves that might have been stuck. Blend again and add additional 2 tbsp olive oil.
In a large skillet with high walls over medium heat, melt 2 tbsp unsalted butter, add in the pesto, and stir to combine. Add in the 3 tbsp of heavy cream and crushed red pepper flakes. Whisk together until the sauce is fully combined. Add in the cooked/drained pasta and using tongs, toss to coat the pasta. Add in 2-3 tbsp of reserves pasta water until the pasta is fully coated with the sauce. Serve with additional cheese over the top.
If you want the sauce more creamy add 1 additional tbsp of heavy cream.
Do not substitute half and half for heavy cream or the consistency will not be the same.