My Healthy Brownie

1 and 1/2 cups dark chocolate chips separated, I use 53% cacao
1/4 cup + 2 tablespoons coconut oil LouAna brand recommended
1 cup vanilla Greek yogurt*
1 teaspoon vanilla extract
1/2 teaspoon salt
1/2 teaspoon baking soda
1/2 cup coconut sugar brown sugar can be substituted
3/4 cup oat flour just blend regular oats in your blender
Optional Frosting:
1/2 cup dark chocolate chips
2 tablespoons unsweetened vanilla almond milk or whatever milk you have on hand
2 tablespoons vanilla Greek yogurt
3/4- 1 & 1/4 cups powdered sugar