Prepare for Baking

1. Preheat your oven to 425°F (220°C).
2. Line a standard 12-cup muffin pan with paper liners.

Make the Streusel Topping

1. In a medium bowl, combine the flour, light brown sugar, granulated sugar, and salt, stirring to mix everything together.
2. Pour the melted butter over the dry ingredients and stir gently with a fork until the mixture looks like coarse crumbs. Set this aside.

Prepare the Muffin Batter

1. In a separate medium bowl, whisk together the flour, salt, baking powder, and baking soda. Set the dry ingredients aside.
2. In a large bowl, using an electric mixer, beat the softened butter and granulated sugar together until the mixture is light and fluffy, about 2-3 minutes.
3. Add the eggs one at a time, beating well after each addition until fully incorporated.
4. Beat in the lemon zest, vanilla extract, and lemon extract until combined.
5. In a small bowl, stir together the Greek yogurt and lemon juice.
6. Add the yogurt mixture to the wet ingredients and mix until just combined.
7. Gradually add the reserved dry ingredients to the wet ingredients. Mix on low speed until just combined. Be careful not to overmix the batter, a few small lumps are fine.

Prepare the Cream Cheese Filling

1. In a clean medium bowl, beat the softened cream cheese with an electric mixer until smooth.
2. Add the granulated sugar and vanilla extract and continue beating until the mixture is smooth and creamy.

Assemble the Muffins

1. Spoon a layer of muffin batter into the bottom of each prepared muffin cup, filling it about one-third full.
2. Place a dollop (about 1-2 tablespoons) of the cream cheese filling on top of the batter in each cup.
3. Cover the cream cheese filling with more muffin batter, filling each cup about two-thirds full.
4. Generously sprinkle the prepared streusel crumb topping over the batter in each cup.

Bake the Muffins

1. Place the muffin pan in the preheated oven, then immediately reduce the oven temperature to 350°F (175°C).
2. Bake for 22 to 25 minutes, or until the muffins are golden brown on top and a toothpick inserted into the cake part (avoiding the cream cheese filling) comes out clean.
3. Let the muffins cool in the pan for a few minutes before transferring them to a wire rack to cool completely.

Make the Glaze

1. While the muffins cool, prepare the glaze by whisking together the powdered sugar and 1 1/2 teaspoons of lemon juice in a small bowl until smooth.
2. If the glaze is too thick, add more lemon juice a few drops at a time until it reaches a pourable consistency.
3. Once the muffins are completely cool, drizzle the lemon glaze over the tops.