In a bowl, toss butter with 3 cups flour until well coated; refrigerate. In a large bowl, combine yeast and remaining flour.
In a saucepan, heat cream, sugar and salt to 120°-130°. Add to yeast mixture with 1 egg. Beat until smooth. Stir in butter mixture just until moistened.
Place dough onto a well-floured surface; roll into a 21×12-in. rectangle. Starting at a short side, fold dough in thirds, forming a 12×7-in. rectangle. Give dough a quarter turn; roll into a 21×12-in. rectangle. Fold into thirds, starting with a short side. Repeat, flouring surface as needed. (Do not chill dough between each rolling and folding.) Cover and chill for 4 to 24 hours or until firm.
For filling, in a bowl, beat egg white until foamy. Gradually add confectioners’ sugar and almond paste; beat until smooth. Cut dough in half widthwise. Roll each portion into a 12-in. square; cut each square into three 12×4-in. strips. Spread about 2 tablespoons filling down center of each strip. Fold long edges together over filling; seal edges and ends. Cut into three pieces.
Place on parchment-lined baking sheets with folded edge facing away from you. With scissors, cut strips 4 times to within 1/2 in. of folded edge; separate slightly. Repeat with remaining dough and filling. Cover and let rise in a warm place until doubled, about 1 hour.
Lightly beat water and remaining egg; brush over dough. Sprinkle with sugar and almonds. Bake at 375° for 15 minutes or until golden brown. Remove from pans to wire racks to cool.