In a microwave safe bowl, add butter and water and microwave for 30 seconds to melt the butter.
Add lemon juice to the butter and stir to combine.
Preheat the oven to 355°F/180°C.
Add eggs and sugar in another bowl.
Whip the eggs with an electric mixer until you can draw thick ribbons. You don't need to work over a hot water bath.
Add melted butter in the egg mixture at once.
Combine with the electric mixer. The butter tends to sink to the bottom. Try to hold the mixer low so that it touches the bottom.
Add flour at once and combine with the electric mixer on low speed, until all flour is incorporated and the batter is smooth.
Pour the batter into the molds.
Bake in a 355°F/180°C oven for 16 minutes. Each oven is different, but they are done when golden brown.
Story Behind this Recipe
I baked this in a poundcake mold and it was too heavy for me. The amount of butter is minimal, but they are moist even right after they are baked.
The batter becomes heavy when you add flour at Step 9. Hold the mixer so that it touches the bottom of the bowl and combine quickly with large movements. When the batter is fluffy and smooth, it's ready.