Dissolve the yeast in 1/4 cup of the warm water. Stir in 1 teaspoon of the sugar and let stand until foamy, about 5 minutes.

Add the remaining water, remaining sugar, butter, egg, and salt. Blend in 1 1/2 cups of the flour. Add enough of the remaining flour, 1/2 cup at a time, to make a workable dough.

On a lightly floured surface or in a mixer with a dough hook, knead the dough, adding more flour as needed, until smooth and springy, about 5 minutes. Place in a greased bowl, turning to coat. Cover loosely with a towel or plastic wrap and let rise in a warm, draft-free place until nearly double in bulk, about 1 1/2 hours, or int eh refrigerator overnight. Punch down the dough.

To make the filling: Beat the butter until smooth, about 1 minute. Gradually beat in the almond paste. Add the sugar and almond extract and beat until smooth.

On a lightly floured surface, roll the dough into an 18-by-12-inch rectanble about 1/4 inch thick. Or divide the dough in half and roll each half into a 12-by-8-inch rectangle. Spread evenly with the filling, leaving a 1-inch border on all sides. Starting from a long side, roll up jelly-roll style, pinching the seams to seal. Place, seam side down, on a lightly greased baking sheet and bend into a horseshoe shape or ring. Cover and let rise until nearly double in bulk, about 45 minutes.

Preheat the oven to 350 degrees F.

Brush the cake with the egg wash. Bake until it is golden brown and sounds hollow when tapped on the bottom, about 40 minutes. If the cake looks as if it is starting to burn, cover loosely with foil, dull side down. Let cool on the baking sheet for 10 minutes, then transfer to a rack to cool.