Step 1: Preheat your oven to 350°F (176°C). Line a standard 12-cup muffin tin with muffin liners or lightly grease each cup.
Step 2: In a medium mixing bowl or the bowl of a stand mixer, combine the cane sugar, softened vegan butter, and lemon zest. Beat with an electric mixer on medium-high for about 2 minutes until the mixture is light, fluffy, and fragrant. The lemon zest will infuse into the butter and sugar during this step — it's where most of the lemon flavour comes from.
Step 3: Add the applesauce, lemon juice, and vanilla extract. Beat on medium until well combined and slightly fluffy. The mixture may look curdled at this point — that's completely fine and expected. It will sort itself out in the next step.
Step 4: Add the almond flour and beat until smooth and fully incorporated. Add the dairy-free milk and mix on low until combined. Finally, add the gluten-free flour blend (or all-purpose flour), baking powder, baking soda, sea salt, and poppy seeds. Mix on medium until the batter is light and fluffy with the poppy seeds evenly distributed throughout.
Step 5: Divide the batter evenly between the 12 muffin liners. Each one should be about ¾ full.
Step 6: Bake for 30–34 minutes until the edges are lightly golden and a toothpick inserted in the centre comes out with just a crumb or two. Don't pull them out too early — underbaked vegan muffins tend to be gummy in the centre.
Step 7: Let the muffins cool completely before eating for the best texture. I know this is hard. Do it anyway.