Step 1

In a pot over medium heat, soften the onion and garlic in the oil for 3 minutes. Add tomatoes and tomato paste and stir to combine. Bring to a boil and simmer for 15 minutes, stirring frequently. Season with salt and pepper.

Step 2

In a blender, purée the sauce until smooth. Return to the pot and keep warm.

Step 3

Meanwhile, in a small pot over medium heat, melt the butter. Add the flour and cook for 1 minute, whisking continuously. Add the milk. Bring to a boil while whisking and simmer for 3 minutes. Season with salt and pepper.

Step 4

Add the bechamel to the tomato sauce and stir to combine. Adjust the seasoning.

Step 5

Meanwhile, in a large pot of salted boiling water, cook the pasta until al dente. Drain. Add to the sauce and stir to coat the pasta in the coat. Divide among shallow bowls and serve immediately.