In a small bowl add all ingredients and stir well to combine. Set aside.

Preheat the oven to 350 degrees F and line a muffin pan with paper liners, set aside.

In a medium-sized bowl add flour, baking powder, fresh thyme leaves, and kosher salt. Whisk to combine and set aside.

In a small bowl (or use your liquid measuring cup) add buttermilk, lemon zest, vanilla bean paste, and lemon extract. Stir to combine and set aside.

In the bowl of an electric mixer add butter and brown sugar.

Bean on medium-high speed until light and fluffy, about 3 minutes.

Add in the eggs, one at a time, scraping down the sides of the bowl between each addition, and mix until just combined.

Lower the mixer speed to low and slowly alternate between adding the flour and buttermilk mixture until all the ingredients have been added.

Gently stir in the fresh blueberries trying not to break them as you stir.

Fill your muffin pans about 3/4 of the way full and smooth the top as best as possible.

Top each muffin with a handful of streusel topping. If the topping sets up a bit (the butter might firm up a bit) just break it up with your hands. You want to use all the topping so don’t be scared to really top those muffins.

Bake for about 25 minutes or until the muffin is fully cooked. You can test your muffin by inserting a toothpick into the center and when removed it should be clean.

Let your muffins cool and top with drizzle.

Whisk together until smooth. If it’s too thick add a little more lemon juice. If it’s too thin add a little more powdered sugar.