Combine rice and 3 cups water in a large saucepan. Bring to a boil. Cover, reduce heat, and simmer 20 minutes or until all liquid is absorbed. Fluff with fork.
Rice (Instant Pot)
Combine rice and 2 cups water in an instant pot. Lock lid. Set valve to sealing. Program for manual-high, and 22 minutes. NPR for best results, but you can do quick release if you're in a hurry. (Note: this can be made ahead, as the IP will automatically switch to keep warm until you're ready to eat.)
Stir Fry
Heat oil in large skillet. Add carrots and radish. Stir fry 2 minutes. Add bell pepper and mushrooms. Stir fry 2 minutes. Add pea pods; stir fry 2 minutes. Stir in corn and stir fry sauce. Stir the cornstarch slurry again, then add to vegetables in skillet. Stir well and continue cooking 2-3 minutes or until sauce is bubbly and thickened. Serve over cooked brown rice.
Stir Fry Sauce
Combine all ingredients except cornstarch in a small bowl. Set aside. Combine cornstarch and 3 Tablespoons water in a separate small bowl. Stir well; set aside.