Heat 1 tablespoon of olive oil in a large skillet over medium heat. Add the zucchini noodles and cook for 2 minutes, stirring frequently, until the noodles are softened. Then drain the noodles in a colander for around 1 minute, squeezing out the excess moisture with the back of a spoon.
Add the noodles back to the pan and stir in the pesto sauce and tomatoes until the noodles are coated.
Notes
Don't overcook the zucchini noodles. They can get soggy and mushy if cooked for too long. Draining the noodles after cooking is critical to avoid watery zoodles. Do not skip that step. You can also blot the zucchini noodles with paper towels to help absorb the excess moisture.