Prepare the Dough: Sift flour into a deep bowl. Add yeast, sugar, and salt. Mix well.
Mix Ingredients: Soften butter and knead into flour. Gradually add milk while kneading. Continue for 10 minutes until smooth.
Rest the Dough: Shape into a ball, cover with a cloth, and let rest 1 hour.
Shape Rings: Divide dough into portions, roll into strips, and join ends to form rings. Place on parchment-lined tray. Brush with egg yolk and sprinkle sesame seeds.
Bake: Preheat oven to 180 C. Bake for 25 minutes or until golden brown. Cool to room temperature before serving.