01 - Combine bread flour, instant yeast, granulated sugar, and salt in a large bowl. Add warm water and melted butter. Mix until a rough dough forms.
02 - Knead dough by hand or with a stand mixer for 8–10 minutes until smooth and elastic.
03 - Place dough in an oiled bowl, cover, and let rise in a warm place for 1 hour until doubled in size.
04 - Mix brown sugar and cinnamon in a small bowl for the filling.
05 - Punch down dough and divide into 8 equal pieces. Roll each piece into a 6x4 inch rectangle. Spread with softened butter and sprinkle with cinnamon-sugar mixture. Roll tightly into a rope, pinch seams to seal, and form into a bagel shape by connecting ends.
06 - Place bagels on a parchment-lined baking sheet. Cover and let rest for 20 minutes.
07 - Preheat oven to 425°F.
08 - Bring a large pot of water to a gentle boil. Add honey. Boil bagels in batches for 1 minute per side.
09 - Transfer boiled bagels back to the baking sheet. Bake for 18–20 minutes until golden brown. Cool on a wire rack.
10 - Mix powdered sugar, milk, and vanilla extract to make glaze. Drizzle over cooled bagels. Immediately sprinkle with purple, green, and gold sugars while glaze is still wet.