Preheat oven to 350 degrees and spray a 6-count muffin tin with baking spray.
In a bowl, mix oats, baking powder, salt, Truvia Baking Blend, and lemon zest together.
In a separate bowl, whisk milk, vanilla extract, lemon juice, oil, and egg together.
Add the wet ingredients into the dry ingredients, and stir until combined. Add in berries, and stir.
Divide the oatmeal batter evenly between the 6-cups.
Bake oatmeal cups for 19-20 minutes, or until the tops are lightly browned and the oatmeal cups are set.
Serve immediately.*
Top with Greek yogurt, fresh fruit, or maple syrup, if desired.
Enjoy!