Position rack in oven middle and preheat to 350°. Oil a 24-cup mini-cupcake pan or two 12-cup mini-pans very well. Do not use paper liners. (If any batter is left over, bake in an oiled ramekin or two.)

Combine lemon zest, 1 teaspoon lemon juice, and milk in a medium bowl. Set aside 5–10 minutes.

Sift flours, sugar, baking powder, baking soda, and salt into a medium bowl. Whisk lightly to aerate ingredients.

Add remaining 3 tablespoons lemon juice, maple syrup, oil, vanilla, lemon extract or oil, and vinegar to almond milk–lemon mixture, and whisk until thoroughly combined. Pour into dry mixture. Whisk until smooth. (Batter will be bubbly.)

Fill each muffin cup two-thirds full. Bake 15–20 minutes, or until sides are lightly golden and an inserted tester comes out clean. Set on a cooling rack. After 5 minutes, invert and allow cakes to fall onto rack. (If they stick, wet a kitchen towel in very hot water, wring it out, and place it on the bottom of pan briefly.) Cool cakes completely.

Mix syrup, lemon juice, and zest (if using) in small bowl. Spoon a teaspoon or two over each cake.