1. Using a spiral vegetable slicer or peeler, cut zucchini lengthwise into long, thin strands (stop when you reach the seeds). Place the strands in a colander and toss with 1/4 tsp. of the salt. Let drain at least 15 minutes, then gently squeeze zucchini to remove any excess moisture. Pile the strands on a cutting board and chop them once or twice to break them up.

2. Meanwhile, cook spaghetti according to package directions. Reserve 1/2 cup of the cooking water; drain pasta.

3. In a small food processor combine basil, walnuts, 5 Tbsp. of the oil, the Parmesan, lemon juice, garlic, pepper, and the remaining 3/4 tsp. salt Process until smooth. Transfer pesto to a large bowl.

4. In a 10-inch skillet heat the remaining 1 Tbsp. oil over medium-high. Add zucchini; cook and stir about 3 minutes or until heated and slightly tender. Transfer to bowl with the pesto. Add spaghetti; toss to combine. If the mixture seems dry, add the reserved pasta cooking water a little at a time. If you like, garnish with additional basil.

*Tip

If you like, skip Step 1 and use 2 lb. refrigerated zucchini noodles.