In a medium pan, set over medium heat, add the cubed bacon and cook until crispy and browned, stirring it every so often, about 5 minutes. Using a slotted spoon, remove the bacon from the pan and transfer it to a paper towel to drain. Turn the heat down to medium low and add the leeks. Cook until the leeks are softened and flimsy but not until they’re overcooked, about 2 to 3 minutes. We still want them to have a lil’ bit of structure. Transfer them to a small bowl.
To a food processor or blender, add the peas, mint leaves, garlic clove, walnuts, olive oil, Pecorino Romano, red pepper flakes and salt. Pulse until the pesto is smooth-ish, some bits of peas are ok. Give it a taste and adjust the flavors to your liking. Add more olive oil if you want it smoother. Add more salt if it needs it. You know, make decisions, you’re in charge.
Bring a large pot of salted water to a boil; cook the pasta according to the package’s instructions. You want al dente. Drain the pasta, transfer it back to the pot and toss with the reserved bacon, leeks and pea pesto. Divide the pasta amongst bowls. Garnish with more cheese because CHEESE! Enjoy this spring pasta. Isn’t spring delicious?