Adjust your oven rack to the 2nd level position (just above center). Preheat your oven to 350ºF and line the middle section of a cupcake tin with 6 cupcake liners.
In a medium-size mixing bowl, whisk together the all-purpose flour, baking powder, and salt. Set to the side.
Using your hand mixer or stand mixer fitted with a paddle attachment, mix together the unsalted butter and granulated sugar on medium-high speed until well blended. Add in the egg and vanilla extract.
Switching the mixer speed to low, add in the whisked dry ingredients followed by the lemon zest, 1 ½ tablespoons of lemon juice, and the buttermilk. Mix until just combined. Do not over mix. The batter should be light in color and easily scoopable into the cupcake liners.
Using a large 3 tablespoon-size cookie scoop (or a serving spoon and regular size spoon), evenly divide the batter into the cupcake liners, filling them about ⅔ full.
Bake for 18-20 minutes at 350ºF or until an insert toothpick comes out clean. They should be yellow in color with light golden brown edges and a relatively flat top.
While the cupcakes bake, whisk together the remaining 1 tablespoon of lemon juice with the 1 tablespoon of honey in a small bowl. When cupcakes are done, remove from the oven and brush the lemon honey mixture over the top of each one with a pastry brush or silicone brush.
Continue to cool the cupcakes in the tin for about 10 minutes. Then transfer to a wire cooling rack to finish cooling. Do not frost the cupcakes until they have cooled.