Asparagus Mushroom Galette

Name: Asparagus Mushroom Galette
Prep time: 45 min
Cook time: 40 min
Total time: 1 h 25 min
Cuisine: European, Mediterranean, French
Ingredients: 1 cup all-purpose flour; 3/4 cup whole-wheat pastry flour; 1 tablespoon sugar; 1/2 teaspoon salt; 3/4 cup cold butter (1 1/2 sticks); 1/3 cup ice cold water; 5 ounces goat cheese, crumbled and divided; 1 tablespoon olive oil; 1/2 onion, diced; 10 ounces sliced cremini mushrooms; 1 bunch asparagus, trimmed and cut into 2-inch pieces; 1 clove garlic, minced; 5 thyme sprigs; Salt and pepper, to taste; 1 egg, beaten with 1 tablespoon water (for egg wash)