Preheat oven to 350 degrees F (180 degrees C).
Microwave the Oat Milk (1 cup) for 30-45 seconds and once warm, add Granulated Sugar (1 tablespoon) and Active Dry Yeast (2 teaspoon). Stir to combine and let it vibe on the side until frothy at room temperature for 15 minutes.
Combine All-Purpose Flour (4 1/2 cup), Granulated Sugar (3 tablespoon), Activated Black Charcoal (4 1/2 teaspoon), and Salt (2 teaspoon) in a large bowl. Once incorporated, make a well in the middle.
Pour in the yeast mixture and Egg (4) into the flour well and combine with a wooden spatula or spoon. Thereafter, add Butter (8 tablespoon) and keep mixing for 10 minutes until the dough takes shape.
Transfer the dough to a lightly floured surface and gently knead it into a soft ball.
Grease another bowl with Olive Oil (2 tablespoon) and place the dough ball in it. Cover with cling wrap and let it rest for 60-90 minutes at room temperature.
After the dough has rested, pour it out onto a lightly floured surface and roll with your hands into a cylindrical shape.
Divide the dough into 8 equal pieces and shape each piece into a well-rounded ball.
Line a baking sheet with parchment paper and place the buns on it with enough space all around. Let it rest for another 30-60 minutes.
Make the egg wash by mixing one Egg (1) with 1 Tbsp of oat milk. Brush each bun with the egg wash and sprinkle Sesame Seeds (to taste) on top. The egg wash helps the sesame seeds stick on the bun.
Bake in the oven for 25-30 minutes until shiny.
Devour while warm with butter or as you please!