Heat a med. saucepan over low heat. Add 5 tbsp butter, ½ cup of water and 2 sliced yellow onions to the pan. Continue to simmer the onions over low heat, stirring occasionally, until they are tender, about 1½ hours. Season with salt then set aside and let cool.
cookingwithcocktailrings.com
In a large pot over medium heat add the olive oil & heat through. Add garlic and sauté, then add tomato paste, tomatoes and sugar, stirring to combine. Simmer for 15 minutes, then season with salt. Add the onion mixture and stir to combine then whisk in the cream, chili paste and chili flakes.
cookingwithcocktailrings.com
Bring a large pot of water to a boil; add the salt and bring back to the boil. Add the pasta and cook, stirring occasionally, until al dente, about 8 min. Reserve 1 cup of the pasta water then drain, and return the pasta to the pot. Ladle sauce over pasta and stir with pasta water
cookingwithcocktailrings.com
Serve the spicy rigatoni hot in warmed pasta bowls.
cookingwithcocktailrings.com