Add 3/4 cup of granulated sugar, and 2 tbsp black sesame seeds to the food processor and run it for 5-10 seconds, or until the sesame seeds are mostly ground. Set to the side.
Mix the cup of flour, 1 1/2 tsp of baking powder, and 1/4 tsp of salt in another small bowl. Set to the side.
Add the three room-temperature eggs to your Kitchenaid mixer fitted with the whisk attachment. Begin whisking them on medium and slowly add the processed granulated sugar with the sesame seeds. After adding all the sugar, turn the mixer up high and whip until it's light yellow and fluffy for about 3 minutes.
Next, add the softened butter to the egg/sugar mixture with the mixer at medium to low speed. Then, turn the mixer up to medium-high and whip for another minute.
Remove the mixing bowl from the stand. Next, you will sift in the flour, adding it in thirds. Sift 1/3 of the flour into the batter and then fold it with a rubber spatula until combined. Repeat two more times until all the flour is combined.
Scoop the filling into either a large pastry bag fitted with a round tip or a large Ziploc bag and then place it in the fridge to cool for at least 2 1/2 hours, up to overnight.
Preheat the oven to 375 degrees. Spray the madeleine pan with oil and then dust it with flour to prevent sticking.
After the madeleine batter has chilled, pipe (or spoon) 1 1/4" circles in the middle of each mold. Place the sheet on the middle rack of your oven and back for 10-12 minutes. The center of each cookie should be rounded and a light golden brown when they are ready to come out!
Remove from the oven and allow to cool in the Madeleine pan for 5 minutes before carefully removing. Finish cooling on a cooling rack.