1-First, preheat your oven to 350 degrees Fahrenheit and line a 12-cup muffin tin with liners to ensure even baking.

2-In a large bowl, combine 1 1/2 cups all-purpose flour, 2 1/2 teaspoons baking powder, and 3 teaspoons cinnamon to create the dry mix.

3-In another bowl, whisk 2 eggs with 3/4 cup brown sugar until smooth, then mix in 1/2 cup melted coconut oil and 1 cup Greek yogurt until well blended.

4-Gently pour the wet ingredients into the dry ingredients and fold them together using a spatula to keep the batter light and airy.

5-Spoon the batter evenly into the muffin liners, filling each about 3/4 full for perfect rising.

6-For the streusel topping, mix 9 tablespoons all-purpose flour, 3 tablespoons brown sugar, 1/2 teaspoon cinnamon, and 4 tablespoons melted unsalted butter in a small bowl until crumbly, then press it onto each muffin.

7-Bake for 18 to 20 minutes or until a toothpick inserted comes out clean. Let the muffins cool on a wire rack.

8-If desired, prepare the glaze by mixing 2 tablespoons powdered sugar with 1 teaspoon water and 1/8 teaspoon lemon juice, then drizzle it over the cooled muffins.