Add chicken thighs to a crockpot and top with canned tomatoes, onions, garlic, capers, oregano, wine, broth and half the rosemary. Turn to low and cook for 4 hours.

Prepare mashed cauliflower. In a medium pot, add 2 inches of water and place on a stove with a lid. Bring to a boil. Add cauliflower to a steamer basket and place in the pot. Steam about 10 minutes, or until cauliflower is soft.

Transfer cauliflower to a food processor. If using an immersion blender, place cauliflower in a large bowl. Add butter and salt. Blend until smooth, scraping sides down as needed. Mixture should be smooth and creamy.

Divide mashed cauliflower among serving plates. Top with chicken cacciatore, olives and fresh rosemary.