For the crumble topping -
3/4 cup flour
1/2 cup rolled oats
1/3 cup sugar
1-2 tbsp orange zest
1/2 tsp vanila
5-6 tbsp butter, cubed
For the muffin batter -
1/3 cup butter or oil, melted
1/3 cup maple syrup
2 large eggs
1 tsp vanilla
1/3 cup Greek yogurt
1/3 cup orange juice
1/3 cup milk (or more yogurt)
1 3/4 cups flour
1 tsp baking soda
1 tsp baking powder
1) Preheat your oven to 375°F.
2) To make the crumble topping, combine the flour, oats, sugar, and orange zest in a small bowl. Add the vanilla and butter. Use your hands or a spoon to combine the butter with the dry ingredients. Set this aside until you are ready to bake.
3) To make the muffin batter, combine the oil and sugar in a large bowl. Whisk in the eggs and vanilla. Then add the yogurt, milk, and orange juice.
4) In a separate small bowl, combine the flour, baking soda, and baking powder. Then add these dry ingredients to the egg mixture and fold together to combine.
5) Grease or line a muffin tin. Fill each cup 3/4 of the way full, then sprinkle on the crumble topping generously. Bake for 22-24 minutes at 375°F, allow to cool, and enjoy!