Preheat oven to 350°F and line a 12-cup muffin tin with paper liners. If your muffin tin is not non-stick, then spray it with cooking spray to prevent the muffin tops from sticking to the pan.
In a large bowl, combine lemon zest and granulated sugar. Mix together with your hands, rubbing the lemon zest into the sugar. This helps to infuse the sugar with lemon flavour.
Add the oil and whisk until combined. Add the eggs, one at a time, whisking after each addition. Add the vanilla, yogurt, and lemon juice, whisking until combined.
Add the flour, almond flour, salt, baking soda, and baking powder. Mix gently using a spatula until no lumps remain. Be careful not to over-mix. Add the poppy seeds and stir gently until evenly distributed.
Fill the muffin tins evenly with the batter. Using a cookie scoop to fill tins works well for me. Bake muffins for 20-22 minutes or until a tester comes out clean. Edges of muffins should just beginning to brown.
Let muffins cool in the pan for 5 minutes, then remove to cool completely on a wire rack. Meanwhile make the glaze (if using) by whisking together all the glaze ingredients until smooth, starting with 1 Tablespoon of milk or cream, and adding more until you reach the desired consistency. Once muffins are mostly cool, drizzle the glaze on tops or spread the glaze on with a knife.