Next, winter storms dump lots of heavy snow on the mountainside. Then wind blows the snow around, breaking it into smaller crystals and depositing a dense layer. To simulate this, cover the granulated sugar layer with half your amount of flour. Pat down the flour and even out the surface. A long cold spell comes along.
More light snow falls onto the hillside.
Model this with the potato flakes, evenly distributing a light layer on top of the flour. Finally, another huge winter storm hits, followed by more wind. Simulate this by using the remaining amount of flour to cover the potato flakes layer. When you are finished, pat down the flour and even out the surface. Now you are ready to simulate your avalanche.