How to Make It
Combine cauliflower, potato, milk, butter and 1 tsp salt in a medium saucepan. Heat over medium-high heat for about 5 minutes or until starting to steam. Cover, reduce heat to medium-low and cook 25 minutes or until potatoes are tender. Place cauliflower mixture in a food processor; process until smooth.
Heat oil in a large 12-inch skillet over medium-high heat. Sprinkle beef and lamb with ½ tsp salt and pepper. Add meat to pan; cook 5 minutes or until browned (do not stir). Remove from pan with a slotted spoon. Add onion and carrots to pan; cook 5 minutes or until onions are tender, stirring occasionally. Add tomato paste; cook 30 seconds, stirring frequently. Add wine; cook 30 seconds or until nearly evaporated, stirring constantly. Add flour to pan; cook 30 seconds, stirring constantly. Add broth and remaining ½ tsp salt to pan; bring to a boil. Cook 1 minute, stirring frequently. Remove from heat and add beef mixture and peas.
Preheat broiler to high with rack 6 inches from broiler.
Place beef mixture in a 2 ½ quart baking dish. Top with cauliflower mixture. Broil 4-6 minutes or until top is lightly browned.