In a large safe nonstick skillet, heat oil over medium-high heat.

Add chicken to pan in two batches, and sear on both sides. 

Transfer to a plate.

Add onion, garlic and rosemary to pan. Sauté 4 minutes, or until onion is softened.

Add wine and bring to a boil. Stir in salt and red pepper flakes.

Return chicken and accumulated juices to skillet. Cook until almost all the wine has evaporated, about 2 minutes.

Add tomatoes and olives.

Cover, reduce heat to low and simmer 30 minutes, to cook chicken through.

Transfer chicken to a serving platter.

Boil sauce 2 minutes to thicken and drizzle over chicken.