Baked Shrimp Tofu Sandwich

Preheat oven to 350 degrees Fahrenheit. Cut tofu into four ½-inch thick, 2-inch long rectangular blocks. You will need two blocks for each sandwich. You can make 8 blocks from ½ pound tofu. Peel and devein shrimp, cut into smaller pieces. Cut shiitake mushroom into few pieces. Put 4 slices of tofu in a baking dish. Use a food processor to blend miso paste, mirin, rice vinegar, grated ginger, shrimp, and mushroom. Evenly divide the shrimp filling among the tofu. Spread some filling on each totu block. Cover the filling with another piece of tofu. Bake for 20 minutes or until shrimp filling is done. Serve plain or on a bed of lettuce. Garnish with green onions.