Add the yeast and warm water to a large bowl. Add the oil and sugar and let stand for about 5 minutes until foamy.

Whisk in the egg.

Stir together the gluten-free flour, salt, and psyllium husk powder, then gradually mix into the wet ingredients. The dough will be soft and slightly sticky, more like thick batter than traditional dough.

Mix for 3–4 minutes with a paddle attachment or sturdy spoon. Gluten-free dough does not need kneading.

Divide the dough into 8 portions and shape into buns with slightly wet hands. Place on a parchment-lined baking sheet.

Cover with a towel and let rest 20–25 minutes to puff slightly.

Preheat oven to 425°F.

Mix the egg yolk and water, brush over the buns, and sprinkle with sesame seeds.

Bake 15–18 minutes, until lightly golden and set.

Let cool at least 15 minutes before slicing.