Preheat the oven to 170°C (338°F).
In a bowl, mix coconut flour, almond flour, and baking powder.
Remove the leaves from the Earl Grey tea bag, grind them into powder, and mix together.
In another bowl, beat the eggs, then add erythritol, vanilla extract, and melted unsalted butter and mix well.
Combine the wet ingredients with the dry ingredients and mix thoroughly.
Fill each madeleine mold up to 80% with the batter.
Bake in the preheated oven for about 15 minutes.
Let cool completely before removing from the pan.