Preheat oven to 400 degrees F. Spray small rimmed baking pan with nonstick spray. Place salmon, skin side down, on prepared pan and sprinkle with ½ teaspoon salt and ¼ teaspoon pepper. Transfer to oven and bake 18 to 20 minutes or until salmon is almost opaque throughout and internal temperature reaches 145 degrees F.

Meanwhile, in a large pot of boiling salted water, cook pasta according to package instructions for al dente, stirring occasionally. Reserve ½ cup pasta cooking water before draining pasta.

Meanwhile, heat butter in large high-sided skillet over medium heat. Add garlic and flour and cook 1 minute, stirring constantly.

While whisking, gradually add broth. Stir in pesto, lemon zest and remaining ½ teaspoon salt and ¼ teaspoon pepper. Heat to boiling over medium-high heat, then reduce heat to medium-low and cook 3 to 4 minutes or until mixture has thickened to a thin sauce consistency, stirring frequently. Reduce heat to low.

Add pasta to skillet, along with ¼ cup pasta cooking water. Cook over low heat, tossing constantly, 1 to 2 minutes or until all pasta is thoroughly coated in sauce. Add additional pasta cooking water, if needed, to keep things saucy!

Remove salmon from oven. Slip spatula between salmon skin and flesh to remove skin; discard skin. Break salmon into large chunks over pasta.

Sprinkle Parmesan cheese and red pepper flakes, if desired, over pasta. Serve garnished with fresh basil and lemon wedges, if desired.