Best Creamy Feta-Lemon Penne With Asparagus Recipe - How To Make Creamy Penne

Ingredients

• Kosher salt
• 8 oz. penne pasta
• 2 tbsp. unsalted butter or extra-virgin olive oil
• 8 oz. asparagus, trimmed, cut into 2" pieces
• 1 large shallot, thinly sliced into rounds
• 2 cloves garlic, thinly sliced
• Finely grated zest of 1 medium lemon (about 2 tsp.), divided
• Freshly ground black pepper
• 1 (5.3-oz.) container plain Greek yogurt (preferably 5% fat or more)
• 4 oz. feta (about 1 c.), crumbled into small pieces, plus more for serving
• 3 tbsp. chopped fresh dill, divided
• 1/4 c. coarsely chopped toasted walnuts