Heat oil and butter in a large heavy pot over medium heat. Add bacon and cook, stirring often, until fat is rendered and bacon is crisp, 5-8 minutes. Add leeks and season with salt. Increase heat to medium-high and cook, stirring often, until leeks begin to brown, 5-8 minutes. Add cream, thyme, and 1/2 cup water. Bring to a boil, reduce heat, and simmer, stirring occasionally, until sauce is thickened and coats the back of a spoon, 5-8 minutes.
Meanwhile, cook pasta in a large pot of boiling salted water, stirring occasionally, until al dente. Drain pasta, reserving 2 cups pasta cooking liquid.
Add pasta, Parmesan, and 1 cup pasta cooking liquid to sauce and stir to coat. Increase heat to medium and continue stirring, adding more cooking liquid as needed, until sauce coats pasta.
Wine, Recipes, Events, and all the latest from the Bumgarners