Roasted Garlic Mashed Potato Topping:

Preheat oven to 350 degrees. Cut off about 1/8 inch at root of unpeeled, garlic bulb. Keeping the shape of garlic bulb lay it on top of a piece of aluminum foil, or place in a garlic roasting dish. Drizzle with 1/2 teaspoon olive oil. Wrap completely in foil (or cover dish) and bake for 50 minutes. Remove from oven and let cool.

Meanwhile, peel potatoes and slice into 1/2-inch rounds. Put potatoes into an 8-quart stock pot. Cover with water and boil for 15 minutes, or until potatoes are soft throughout. and drain. In a large mixing bowl, or in stock pot, add soy milk to potatoes. Puree potatoes using an electric hand mixer. Once garlic has cooled enough to handle, squeeze each roasted clove into potatoes. Add 1/2 teaspoon salt and 1/4 teaspoon black pepper and mix well.

Portabella Boca Base:

Heat oil in a large saucepan or stockpot. Saute onion over medium-low heat for 3 minutes. Using a garlic press, crush 2 cloves of garlic directly into pot. Stir in mushrooms, cover and cook for 5 minutes. Add Boca Burger Crumbles (if using), baby carrots, and celery. Stir in 1/2 cup vegetable broth, reserving remaining 1/4 cup for later. Add soy sauce, fresh rosemary, salt and pepper. Cover and cook for 15 minutes. Remove from heat. In a small mixing bowl, slowly add remaining 1/4 cup broth to flour. Add to mushroom mixture and cook to thicken. Finally, stir in frozen peas.

Assembling the Shepherd's Pie:

Preheat oven to 350 degrees. Spray a casserole dish or an 11x8" baking dish with non-stick cooking spray. Pour Portabella Boca Base into dish. Spread Roasted Garlic Mashed Potatoes on top. Smooth out potato topping or "rake" with a fork to create an interesting presentation. Bake uncovered, for 30 minutes. Garnish with fresh rosemary sprigs and serve hot.