Step 1

Preheat oven to 375˚.

Step 2

In a large bowl add the Vinegar, Lemon juice, Mustard, Garlic, Herbes De Provence, Salt and Pepper.

Step 3

Slowly whisk in the oil.

Step 4

Add the Mushrooms and Potatoes and toss to coat.

Step 5

Place on a greased baking sheet and bake at 375˚ flipping over for even roasting every 15 minutes until potatoes are golden brown and the mushrooms have darkened, about 45 minutes.

Step 6

Serve hot.