Vegan Galette with Caramelized Onion and Vegetables

Ingredients (for 16 servings)

• 1 cup — cauliflower florets
• 1 cup — butternut squash
• 1 cup — shiitake mushrooms
• 4 sprig — thyme
• 2 whole — onions
• 0.75 cup — whole wheat flour
• 0 — Pinch sea salt
• 1.5 tbsp — tahini
• 1 tsp — apple cider vinegar