Preheat oven to 350ºF. Line a muffin tin with paper liners and set aside.
Beat together the wet ingredients until smooth and creamy.
Add the dry ingredients to the bowl and stir together. Fold in lemon zest and poppy seeds.
Fill the muffin tins 3/4 of the way full. This recipe yields between 9 and 10 muffins, so fill any empty tins with a splash of water.
Bake on the center rack for 21 - 23 minutes, until a cake tester inserted into the center comes out clean.
While the muffins are baking, make the icing. Melt all the icing ingredients in a small pan over low heat. Whisk constantly until you get a smooth texture. Add a dash more almond milk if needed to thin it out.
When muffins are done baking, allow to cool completely before icing.
Store these muffins in an airtight container at room temperature for 3 to 4 days.