A small yeasted coffee cake made in a bread loaf pan.
Add the flour, sugar, salt, and yeast in a bowl.
Heat water and butter to 130-degrees. Stir in the egg yolk and vanilla. Pour this mixture over the flour mixture.
Stir the dough together. Spread it in a greased loaf pan and let it rise.
Make the streusel and spread it over the dough. Bake and let cool. Then, make the drizzle and pour it over the cake.