Oma's Marzipan Stollen

In a large bowl, combine 2 cups flour, sugar and yeast. In a small saucepan, heat milk and butter to 120degrees-130degrees. Add to dry ingredients; beat just until moistened. Add lemon zest; beat until smooth. Stir in enough remaining flour to form a soft dough (dough will be sticky)., Turn onto a floured surface; knead until smooth and elastic, 6-8 minutes. Place in a greased bowl, turning once to grease the top. Cover and let rise in a warm place until doubled, about 1 hour., For filling, in a large bowl, beat almond pastry filling, almonds, milk and extract. Punch dough down; turn onto a floured surface. Divide into thirds. Roll each portion into a 15x6-in. rectangle. Spread each portion with a third of the filling to within 1/4 in. of edges. Roll up jelly-roll style, starting with a long slide; pinch seam to seal. Place ropes on a parchment-lined baking sheet. Using a sharp knife, make a 1/2-in.-deep cut lengthwise down the center of each rope, stopping 1/2 in. from ends. Keeping cut surfaces facing up, braid ropes. Pinch ends to seal; tuck under., Cover with a kitchen towel; let rise in a warm place until almost doubled, about 30 minutes. Preheat oven to 375degrees. Bake until golden brown, 30-35 minutes. Remove to a wire rack to cool. Combine glaze ingredients to desired consistency; drizzle over warm stollen.