In a small bowl, cream the butter, brown sugar and cinnamon until light and fluffy. Stir in toffee bits.

Separate each tube of crescent dough into four rectangles (If using the non-perforated vesion - just cut into 4 rectangles); seal perforations. Spread evenly with butter mixture. Roll up each rectangle jelly-roll style, starting with a long side.

Cut each into six 1-in. slices; place cut side down into two greased 8-in. square baking dishes. Bake at 375° for 14-16 minutes or until golden brown.

In a small bowl, combine the confectioners' sugar, milk and vanilla until smooth. Drizzle over warm rolls. Yield: 4 dozen.