Step 1In a mixing bowl, combine the almond meal, flour, powdered sugar and baking powder. Set aside.
Step 2Split the vanilla bean lengthwise and scrape the seeds into a small saucepan. Add the scraped pod and butter; over medium heat, melt the butter and cook until golden brown, 6 to 7 minutes. Remove the pod and allow the butter to cool.
Step 3Add the egg whites to the dry ingredients and combine well. Add the honey, then the brown butter and orange zest and mix until well combined. Chill the batter at least 2 hours. (Keep batter chilled between baking batches.)
Step 4Heat the oven to 350 degrees. Grease a nonstick mini madeleine mold with soft butter or cooking spray (if using butter, grease the mold twice). Fill a pastry bag fitted with a medium round (No. 4) tip. Pipe a small amount, about the size of a quarter, into the molds. The batter should not reach the edges of the mold as it will spread. Bake until brown at the edges, about 10 minutes.
Step 5Let rest for 1 minute and unmold the madeleines. Serve immediately. (Be sure to store them so that they don't touch each other as they will stick together.)