In a nonstick skillet heat oil over medium high heat. Sauté onion, bell pepper, cumin, salt and pepper until light and translucent, about 5 minutes. Add garlic and cook additional 1 minute. Add diced tomatoes, reduce heat and simmer until thick. Stir in shredded chicken, remove skillet from heat and place in bowl.

Divide mixture evenly among tortillas. Gently fold in edges and roll up. Wipe non stick skillet clean, return to medium high heat and add 1 tablespoon olive oil to pan. Lightly fry chimichangas in batches until crispy and lightly browned on each side, adding additional olive oil to pan if necessary.

In a small bowl combine avocado, sour cream and lime juice. Mash with a fork until smooth; serve over warm chimichangas garnished with fresh cilantro.