In a blender, cover and process cottage cheese until smooth. Add the sugar, milk, oil and vanilla; process until smooth. Combine the flour, baking powder and salt; add to cheese mixture. Process just until dough forms a ball (dough will be sticky). Turn onto a floured surface; knead 4-5 times. Place in a large bowl; cover and refrigerate for 30 minutes.
In a large bowl, beat cream cheese and sugar until smooth. Beat in the egg yolk, lemon zest and vanilla. Turn dough onto a 17x13-in. piece of parchment. Roll into a 16x12-in. rectangle. Transfer with paper to a baking sheet.
Spread cream cheese mixture lengthwise in a 3-1/2-in.-wide strip down center of dough; sprinkle with blueberries. On each long side, cut 1-in.-wide strips about 3-3/4 in. into center. Fold alternating strips at an angle across berries. Pinch ends to seal and tuck under. Beat egg white and water; brush over dough.
Bake at 400° for 20-22 minutes or until golden brown. Remove to a wire rack. Combine glaze ingredients; drizzle over warm pastry. Refrigerate leftovers.
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