Pesto pasta is wonderful, but sometimes it can feel a little oily. This Creamy Pesto Pasta fixes that with a quick white sauce made from butter, flour, and milk, so the pesto turns into a smooth, velvety coating that clings to every noodle. There is no heavy cream needed, it uses just a handful of ingredients, and dinner is ready in about 25 minutes. It is a favorite with kids and a great base for adding chicken, shrimp, or vegetables. If you like a different take, try my Creamy Pesto Chicken Pasta.
Table of Contents
Why This Creamy Pesto Pasta Works
- A white sauce base: the butter, flour, and milk roux gives you a creamy sauce without heavy cream.
- Pesto stirred in off the heat: adding the pesto at the end keeps its bright basil flavor and green color.
- Ready in 25 minutes: the sauce cooks while the pasta boils.
- Easy to adapt: use any pasta shape, add protein or vegetables, or swap in sun-dried tomato pesto.
A white sauce, or béchamel, is a cooked mixture of flour and butter (a roux) thickened with milk. It is a classic base for creamy dishes because it stays smooth and reheats well, which makes it more forgiving than cream-only sauces.
Ingredients for Creamy Pesto Pasta
- 12 ounces pasta, such as penne, fusilli, or fettuccine
- 1/4 cup (4 tablespoons) butter
- 1/4 cup all-purpose flour
- 2 cups whole milk, at room temperature
- 1/2 cup basil pesto, store-bought or homemade
- 1/2 cup grated Parmesan cheese, plus more for serving
- 1/4 to 1/2 teaspoon salt, to taste
- 1/4 teaspoon black pepper
- Reserved pasta water, as needed
- Fresh basil and toasted pine nuts, for garnish (optional)
Store-bought pesto is salty, so taste the sauce before adding salt. If you make your own, try my Homemade Basil Pesto.
How to Make Creamy Pesto Pasta
Step 1: Boil the Pasta
Bring a large pot of generously salted water to a boil and cook the pasta according to the package directions until al dente. Scoop out 1 cup of pasta water, then drain.
Step 2: Make the Roux
While the pasta cooks, melt the butter in a medium saucepan over medium heat. Whisk in the flour and cook, stirring constantly, for 1 to 2 minutes, until it smells lightly toasty and bubbles gently. Do not let it brown.
Step 3: Whisk in the Milk
Slowly pour in the milk, about 1/2 cup at a time, whisking constantly to prevent lumps. Turn the heat to medium-high and cook, stirring, for 3 to 5 minutes, until the sauce is thick enough to coat the back of a spoon.
Step 4: Add the Cheese and Pesto
Remove the pan from the heat. Stir in the Parmesan until melted, then whisk in the pesto. Season with salt and pepper. Adding the pesto off the heat helps it keep its fresh flavor and bright green color.
Step 5: Toss and Serve
Return the drained pasta to its pot, pour the sauce over it, and toss until coated. If the sauce is too thick, loosen it with pasta water a splash at a time. Serve immediately with extra Parmesan and basil.
How to Serve Creamy Pesto Pasta
Top the pasta with fresh basil, extra Parmesan, cracked pepper, and toasted pine nuts. Add grilled chicken, sauteed shrimp, or roasted cherry tomatoes to turn it into a full meal, or use my Sun-Dried Tomato Chicken Pesto Pasta for an even heartier version. A crisp green salad and garlic bread round out the plate.
How to Store and Reheat Leftovers
Cool the pasta and refrigerate it in an airtight container within 2 hours. According to the USDA, leftovers are best eaten within 3 to 4 days. The pasta absorbs sauce as it sits, so reheat it in a skillet over medium-low heat with a splash of milk or water and stir until creamy again. You can also microwave it in short intervals, stirring in between. For freezing, freeze the sauce alone for up to 2 months, then thaw it and toss it with fresh pasta.
Tips and Variations
- Use room-temperature milk. Cold milk can cause lumps when it hits the hot roux.
- Add the pesto off the heat. Cooking it dulls the color and can make the basil taste bitter.
- Adjust the thickness with pasta water. The starch helps the sauce cling.
- Add 2 cloves of minced garlic to the butter before the flour for extra flavor.
- Stir in baby spinach, peas, or sauteed mushrooms for vegetables.
- Use sun-dried tomato pesto or red pesto for a different flavor.
- For a gluten-free version, use a 1-to-1 gluten-free flour and gluten-free pasta.
Frequently Asked Questions
Can I make creamy pesto pasta without cream?
Yes. The butter, flour, and milk white sauce gives a creamy texture without cream.
Why is my sauce lumpy?
The milk was added too quickly or was too cold. Whisk constantly, add the milk gradually, and use a whisk to smooth any small lumps.
Can I use homemade pesto?
Yes. Homemade pesto is usually less salty than store-bought, so taste the sauce and add salt as needed.
What pasta works best?
Shapes with ridges or curves, such as penne, fusilli, and rotini, hold the sauce well. Long pasta like fettuccine also works.
Can I add chicken or shrimp?
Yes. Cook the protein separately, then stir it into the pasta at the end.
Creamy Pesto Pasta
Ingredients
Main Ingredients
- 12 ounces pasta Penne, fusilli, or fettuccine.
- ¼ cup butter
- ¼ cup all-purpose flour Use a 1-to-1 gluten-free flour if needed.
- 2 cups whole milk Room temperature.
- ½ cup basil pesto Store-bought or homemade.
- ½ cup grated Parmesan cheese Plus more for serving.
- ¼ to ½ teaspoon salt To taste; pesto is salty.
- ¼ teaspoon black pepper
- reserved pasta water As needed to loosen the sauce.
- fresh basil and toasted pine nuts Optional, for garnish.
Instructions
Cooking
- Cook the pasta in generously salted water until al dente. Reserve 1 cup of pasta water and drain.
- Melt the butter in a medium saucepan over medium heat. Whisk in the flour and cook 1 to 2 minutes without browning.
- Slowly whisk in the milk, about 1/2 cup at a time. Cook over medium-high heat, stirring, 3 to 5 minutes until thick enough to coat a spoon.
- Remove from the heat. Stir in the Parmesan until melted, then whisk in the pesto. Season with salt and pepper.
- Toss the sauce with the pasta, loosening with pasta water as needed. Serve with extra Parmesan and basil.
