Preheat oven to 375°F (190°C). Grease a 12-cup muffin tin or line with paper liners.
In a large bowl, whisk together the flour, baking powder, baking soda, salt, and poppy seeds.
In a separate bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, then stir in the sour cream, vanilla, lemon juice, and lemon zest.
Gradually add the dry ingredients to the wet ingredients and mix until just combined. Do not over mix.
Fill the prepared muffin tin with the batter. Bake for 18-20 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Remove from the oven and let cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.
Interesting Facts
Poppy seeds are a nutrient-rich source of minerals, vitamins, and essential fatty acids.
Lemon juice is a great source of vitamin C, which helps support the immune system.
Muffins are a great way to use up leftovers, like overripe bananas or apples.