Flip the mini pie tins right side up; arrange one dough circle in each tin. Prick the dough with a fork on both the sides and the bottom. Place a small piece of parchment paper on top of each dough-filled tin and pour enough baking beans on top of each piece of parchment to fill the tin to the rim. Press the beans down gently to ensure it reaches into the bottom and corners. Transfer to the preheated oven and bake for 10 minutes or until the pie dough is crisp and light brown in color. Remove from the oven and lift the beans out by gathering the corners of the parchment paper. Let the crusts cool slightly.
In a medium bowl, toss together the flour and Swiss cheese. Add the spinach and mushrooms, toss to combine and reserve. In another medium bowl, beat the eggs with the evaporated milk, salt, white pepper and dry mustard. Divide the cheese and vegetable mixture between the baked crusts; pour the egg mixture over the cheese and vegetables. Transfer to the oven and bake 15 minutes, or until puffed and golden brown. Remove from oven and eat warm or at room temperature.
While the quiches are baking, prepare the wild mixed greens and fresh raspberry vinaigrette: In a medium bowl, mash together 1/2 of the raspberries and the sugar with a fork. Add champagne vinegar, then whisk in the oil. Season with a little salt and pepper.
When ready to serve, toss greens with the vinaigrette and garnish with remaining raspberries and toasted walnuts and serve alongside your quiches.