Preheat oven to 350 degrees. Grease a 12-cup muffin tin with coconut oil or use parchment paper baking cups.
Place all ingredients (except for 1 tbsp. of lemon zest and ½ poppy seed for garnish) into a bowl and beat until well mixed.
Fill each muffin cup half full with batter and bake for 20-25 minutes. Remove from oven and allow muffins to cool on a wire rack.
Meanwhile whisk glaze ingredients in a bowl and brush the tops of the cooled muffins. Sprinkle with the reserved lemon zest and poppy seeds.