Melt butter with oil in a large saucepan over medium heat
When butter foams, add onion, carrot, celery and pancetta
Sauté until lightly browned
Add veal and cook, stirring, until meat is no longer pink
Season with salt and pepper
Increase heat to high and stir in wine
Cook until wine has evaporated
Press tomatoes through a food mill or sieve to remove seeds
Stir tomato pulp into veal mixture
Cover and reduce heat
Simmer 1 to 1 ½ hours or until sauce reaches a medium-thick consistency, stirring occasionally during cooking
Add milk and cook 5 minutes longer, stirring occasionally