- Cut rhubarb into 1/2 inch pieces. Blanch the pieces in boiling water for 1 and 1/2 minutes, drain and pat dry.
- Place 1 sheet of phyllo on a baking sheet the same size as the phyllo dough.
- Brush with butter and sprinkle with a few tablespoons of the amaretti crumbs.
- Keep remaining dough covered with damp towel to prvent from drying out.
- Layer 4 more sheets of the phyllo on top of the first in the same manner, brushing each with butter and sprinkling with crumbs.
- Then, layer 2 more sheets, brushing with butter but omitting the amaretti.
- Mak a compact row of rhubarb peices 2 inches from one long edge of the dough.
- Sprinkle the rhubarb with the brown sugar, cinnamon, orange zest, walnuts and any remaining amaretti crumbs.
- Layer 2 more phyllo sheets over the rhubarb, brushing with butter.
- Starting at the edge with the rhubarb, roll up the dough like a jelly roll.
- Turn seam side up and brush the top and sides of the dough with butter.
- Turn seam side down, fold both ends under to seal, and brush top with butter.
- Bake until golden brown (40-50 minues).
- Let stand several minutes, then slice.
- Serve with whipped cream or ice cream.
- Can be baked in advance and served at room temperature or cold.