Bring a large pot of salted water to a boil and cook the 8 ounces DeLallo Bucatini Pasta al dente according to package directions.
While the pasta cooks, place the drained 1 (12 ounce) jar DeLallo Roasted Red Peppers, 2–3 cloves minced garlic, 1/4 teaspoon Italian seasoning, and 1 tablespoon DeLallo Extra Virgin Olive Oil in a food processor; blend until smooth.
In a skillet over medium heat, melt 1 tablespoon butter. Add 1/2 medium chopped onion and cook, stirring occasionally, until softened and lightly browned, about 4–5 minutes.
Add the red pepper puree, 3/4 cup heavy/whipping cream, and 1/2 teaspoon Dijon mustard to the skillet. Cook, stirring occasionally, until the sauce has thickened slightly, about 7–8 minutes. Taste and season with salt and pepper.
Just before draining the pasta, reserve some of the hot pasta cooking water (set it aside in a cup or bowl). Drain the pasta in a colander.
Stir 2 cups (packed) fresh baby spinach and 1 small handful fresh basil (torn or roughly chopped) into the sauce until the spinach begins to wilt.
Add the drained pasta to the skillet and toss to coat. If the sauce is too thick, add a little of the reserved pasta water, a splash at a time, until you reach the desired consistency and the spinach is fully wilted.
Serve immediately with freshly grated parmesan cheese to taste and additional salt and pepper if needed.