Heat a heavy-bottomed skillet on medium heat, and add the sliced butter, making sure to whisk frequently to prevent the butter from burning. The melted butter should start to foam up a little bit, and then subside. Watch the butter carefully as lightly browned specks begin to form at the bottom of the pan.
Once the butter has turned into a lovely light amber color and is emitting a nutty aroma, remove from heat and place on a cool surface to help stop the butter from cooking further and burning. Set aside to cool.
Combine 1 1/2 cups flour and 1 teaspoon baking powder in a medium bowl, whisking together. Set aside.
Use an electric mixer with a whisk attachment (or, use a handheld whisk) on medium-high speed to beat together the eggs, sugar, and honey. This should take about 5 minutes, and the mixture should increase in size and become pale in color by the end of the beating process.
Sift the flour and baking powder mixture over the top of the egg/sugar/honey mixture, before using a rubber spatula to gently fold the flour into the egg/sugar/honey mixture until just combined. There should be one or two flour streaks still in the mixture.
Once the flour has just been combined into egg/sugar/honey mixture, fold in the cooled browned butter and mix until just combined.
Cover the batter and refrigerate for about 1 hour or until completely chilled.
Preheat the oven to 375 (F). Generously butter your madeleine pan, making sure that all the interior surfaces of the shell molds are well buttered. Use a cookie scoop to spoon batter into the molds, filling each only about 2/3s of the way. My pan required about 1 tablespoon of batter per mold.
Bake for about 12 - 15 minutes until the edges are golden brown. Transfer the pan to a cooling rack for 5 minutes before unmolding the cakes onto a cooling rack.
Dust the madeleines with powdered sugar just before serving.
If you're using a traditional madeleines pan make sure to grease your pan well so the cakes don't stick to the pan and to give a crispy exterior to the cakes.