Starting a fire in deep snow can be an intimidating chore, but it doesn't need to be. This past weekend, at a scouting event, I kept myself busy while the scouts were doing activities by building this fire.
First I put a layer of 4" wood on the bottom, tightly placed. This layer acts as as a retention layer for the heat and coals until the fire is going well. Eventually it will burn through but at that point you will have a good layer of coals and ash that will keep the fire lit.
Second, I added a top border of 2" wood around the edge of the fire. This helps to keep the fire in place and retains the coals a little better.
Last I built the fire using "old man's beard" as a tinder, followed by progressively bigger twigs and then branches. The twigs and branches were from a nice and dry standing dead spruce.
The fire will continue to melt down until it his the ground, it took approximately 4 hours for the fire to make it's way to the ground in this case. There was approximately 1m of snow.