In a large saucepan of 2 cups water, cook rice according to package instructions; set aside.
Preheat oven to 400 degrees F. Lightly oil a baking sheet or coat with nonstick spray.
Place tomatoes in a single layer onto the prepared baking sheet. Add 2 tablespoons olive oil and oregano; season with salt and pepper, to taste. Gently toss to combine.
Place into oven and bake until the tomatoes begin to burst and have softened, about 15-16 minutes; set aside.
In a large pot of boiling salted water, blanch green beans until bright green in color, about 2 minutes. Drain well and cool in a bowl of ice water. Drain well and set aside.
Heat remaining 1 tablespoon olive oil in a large skillet over medium heat. Season chicken with salt and pepper, to taste. Add to skillet and cook until golden, about 3-4 minutes. Stir in pesto and gently toss to combine.
Serve chicken immediately with rice, tomatoes and green beans.