Preheat oven to 425 F.
In a bowl, lightly toss potatoes and squash with 1/2 tsp rosemary, 1/4 tsp salt and 1/4 tsp black pepper.
Place on a baking sheet misted with cooking spray.
Drizzle with 2 tsp oil, tossing gently.
Bake for 25 minutes or until tender, stirring every 10 minutes.
Heat remaining 2 tsp oil in a large nonstick skillet over medium-high.
Saute shallots, broccoli and bell peppers for 1 minute.
Add potato-squash mixture and cook for 5 minutes or until heated.
Sprinkle with lemon juice, remaining 1/2 tsp rosemary, 1/4 tsp salt and 1/4 tsp black pepper and heat through.