Place your tomatoes and mushrooms in your bowl. Take your asparagus, cut an inch off the bottoms and throw away. Then cut into thirds and add to your bowl.
Now take your chicken breast and cut it into as even as possible 1-2 inch cubes. You want them to be as similar in size as possible for even cooking.
Place in your bowl with the vegetables. Now add 1/4 cup pesto sauce, use a spoon and mix until everything is evenly coated with sauce.
Lightly coat your baking sheet with olive oil to prevent sticking. Now add everything from the bowl onto the sheet and spread out for even cooking. Bake for 20-25 minutes, until the chicken is done.