Heat milk and sugar in microwave for 40 secs, stir in yeast to combine, and let stand for 10 minutes
In a bowl, mix flour and salt, then mix in paste and oil. Pour in bubble yeast, knead.
Cover with cling wrap, let rest at least 30 minutes or until doubled in size.
Divide dough per 100 g, roll flat into oval and place a wiener in center. Seam to seal.
Slice without cutting through and pull slices like a zigzag, and bring end to end shaping into a round.
Spoon mayo into a ziplock bag, set to side. In a small bowl, mix enough ketchup and Srirach, spoon into a different ziplock bag.
Preheat oven to 375 F.
Snip one corner of each ziplock bag of the mayo and ketchup mixture. Top each bun with mayo and ketchup.
Bake buns for 20-22 minutes