Melt the butter and set aside so it can cool down (we don’t want to use it hot). You can use the microwave (do 30 seconds by 30 seconds and stir) or on the stovetop).
Warm the milk (it shouldn’t be hot, just lukewarm).
Stir with a whisk the eggs, sugar and honey. Add the milk (lukewarm, about 68F).
Mix the flour and baking powder and add to your previous mix, gently folding (add in 3 times).
Stir the butter little by little and add either a grated vanilla bean or a tsp of pure vanilla extract.
Add the zest of half a lemon, stir until everything is well incorporated.
Cover the batter with plastic wrap (the plastic should touch the batter to avoid forming a crust) and refrigerate for 1h30 (or overnight).
Grease and flour your pan to avoid any chances of the madeleines sticking to it.
Use a pipping bag (or a spoon) to fill the mold. You want to add the batter right in the middle of the mold. Don’t overfill, just two third is enough. No need to spread the batter, it will expand by itself while baking.
Bake for about 12 minutes at 374F (190C).
Enjoy warm with a glass of cold milk or with your coffee/tea.