Heat oil in a Dutch oven over medium-high heat. Add mushrooms and onions; sauté 3 minutes. Add rice; sauté 2 minutes. Add water, salt, pepper, and broth; bring to a boil. Cover, reduce heat, and simmer 20 minutes or until liquid is absorbed.
Stir in corn. Cover and cook 5 minutes. Remove from heat; stir in Classic Pesto.