• In a small saucepan, melt the butter then set aside to cool to room temperature while preparing the madeleine cookie batter.
• In a small bowl, add the flour, baking powder, and salt and whisk to combine.
• Add the eggs and sugar to the bowl of an electric mixer. Beat on high speed for 5 to 8 minutes or until thick and pale in color. Add the ground lavender buds and the lemon zest, mix until combined. 
• Sift 1/3 of the flour mixture over the top of the egg mixture and gently fold it together. Repeat with the remaining flour in increments of 1/3 each time. 
• Scoop out about one cup of the batter and fold into the melted butter, (this lightens the butter and will make it easier to fold into the whole batch). Then add the mixture to the batter and fold together gently. Fold in a few drops of lavender oil (add 1 to 2 drops for a light lavender favor then taste the batter to see if you want more).
• Cover the batter with plastic wrap, pressing right down onto the batter, then transfer to the refrigerator. The batter should rest for at least one hour but overnight if possible. The batter can be refrigerated for up to 3 days before baking. 

When ready to bake the madeleines:

• Preheat the oven to 375°F and grease and flour the madeleine pan.
• Remove the batter from the refrigerator and using a small ice cream scoop or a tablespoon, drop a small portion about the size of a walnut into each shell-shape indentation of the pan. 
• Transfer the madeleine pan to the center rack of the oven and bake for 7-8 minutes, until the edges look golden and crisp and the cakes spring back when lightly touched.  If using baking powder it may take another 30 seconds to 1 minute longer.  Remove from the oven and immediately flip them onto a kitchen towel then place on a wire rack to cool. 

To Make the Lavender Glaze:

• Mix the confectioners’ sugar with 3 tablespoons of water. Stir until smooth and add additional water a tablespoon at a time until you have a thin mixture.
•  Add several drops of lavender oil, tasting the glaze before adding additional drops. Be cautious as it is easy to over flavor.