Shiitake Mushroom and Steak Flatbread on Shiitake Crust

Ingredients

• 2 oz dried shiitake mushrooms, stems removed
• 2 cups all purpose flour
• 1 tsp salt
• 1/3 cup + 2 tbsp vegetable shortening
• 3/4-1 cup water
• 2 tbsp butter
• 2 tbsp fresh rosemary, minced
• 1 large leek, sliced thinly into half moons
• 200 g fresh shiitake mushrooms, sliced and woody, stems removed
• 1 clove garlic, minced
• 1 tbsp Dijon mustard
• 1/3 cup white wine
• kosher salt to taste
• fresh cracked black pepper to taste
• 1/4 cup heavy cream (or half and half)
• 1/2 lb. hanger steak (or any good quality steak such as, filet, strip, ribeye, etc.)
• 1 tsp olive oil
• 200 g Gruyere cheese, grated fine
• 3 oz fresh baby spinach, roughly chopped
• 1 tbsp butter