Preheat your oven to 400°F (200°C) to get it nice and hot for perfect muffin rising. Grease a 12-cup muffin pan or line it with muffin liners (parchment liners work great too!).

In a small bowl or measuring cup, mix together milk and Greek yogurt. Let it sit for about 5 minutes while you prepare everything else. This simple hack helps create super tender muffins!

For the streusel, mix flour, brown sugar, and cinnamon in a medium bowl. 

Cut cold butter into small cubes and work it into the dry ingredients with your fingers until you get a crumbly texture with both sandy bits and larger crumbs. 

Chill the streusel in the fridge while you work on the muffin batter to keep it extra crisp.

In a large bowl, whisk together the flour, sugar, baking powder, baking soda, cinnamon, nutmeg, and salt, this is the magical step where all the comforting flavors come to life!

Add eggs, oil, maple syrup, vanilla, and lemon zest to the milk-yogurt mixture. Whisk until smooth, the lemon zest adds a beautiful depth of flavor without making the muffins taste lemony.

Pour the wet ingredients into the dry ingredients and gently stir together using a spatula. Don't overmix, lumps are totally fine and will make your muffins soft and fluffy.

Spoon the batter into the muffin cups, filling them about ¾ of the way. Generously sprinkle the chilled streusel over each muffin before baking.

Bake the muffins for about 15-17 minutes or until the tops are golden brown and a toothpick comes out clean. 

Allow them to rest in the pan for 5 minutes before moving them to a wire rack to cool fully.

While they cool, mix powdered sugar, vanilla, and milk for the glaze. Once the muffins are completely cooled, drizzle the glaze on top, go as light or thick as you like!

Now, you've got a batch of coffee cake muffins ready to enjoy!