Heat oil in large nonstick skillet over medium-high heat. Add peppers and onions; saute until onions are deep golden, about 10 minutes. Add garlic, thyme, and orange peel; stir 1 minute. Add shrimp and peas; sprinkle with salt and pepper. Saute until shrimp are just opaque in center and peas are heated through, about 4 minutes. Season to taste with salt and pepper. Meanwhile, cook pasta in large pot of boiling salted water until just tender but still firm to bite, stirring occasionally. Ladle out 1/2 cup pasta cooking water and reserve. Drain pasta; return to pot. Add shrimp mixture and reserved cooking water to pasta; toss to blend. Season to taste with salt and pepper. Transfer pasta to bowl and serve.