Cook fettuccine pasta per package directions until al dente. Heat 1 tbsp olive oil and 1 tbsp butter over high heat in a skillet until foamy. Sprinkle 12 scallops with a little salt and pepper; place in skillet in single layer. Cook, turning once, until brown on outside and just opaque in center, about 2 minutes per side. Remove from pan and set aside. Drain pasta and return to the pot over low heat. Stir in zest of one lemon, 1/2 c. lemon juice, 3 tbsp olive oil, 1 1/2 c. peas, and 4 tbsp fresh thyme. Toss to coat, then season with salt and lots of pepper. Add 1 container ricotta and mix gently until pasta is coated evenly. To serve, divide the pasta between four plates, topping each with three scallops and a sprig of fresh thyme.