Final answer:
Sirloin beef tips and gravy is the dish that is usually paired with brown butter mashed potatoes and garlic rosemary mushrooms, as this combination offers a harmonious blend of flavors suitable for a savory meal.
Step-by-step explanation:
The dish that is typically served with brown butter mashed potatoes and garlic rosemary mushrooms is a sirloin beef tips and gravy. This choice pairs well with the rich flavor of the brown butter in the mashed potatoes and the aromatic garlic and rosemary in the mushrooms. Sirloin beef tips are a common protein selection for a hearty and savory gravy-based dish, complementing the other components of the meal.