In a medium bowl toss beef with flour. Add to a 4 to 6-quart slow cooker along with the tomatoes, potatoes, salt, pepper and 1/2 cup water. Cook on low for 7-8 hours (or on high for 5 hours).
Stir in peas and carrots and let sit for 5 minutes. Transfer the stew to a food processor or blender and puree to desired consistency for baby. Leave the stew chunky for toddlers and grown-ups.