Crust: Make your own or buy one to fit a 9" spring form pie pan.
Filling: 2 1/4 lbs. medium-size red-skinned yams(about 4)
1 3/4 cups sweetened condensed milk (2 14oz cans)
1/2 cup sugar
5 Tbls. (3/4 stick) unsalted butter, melted
1/4 cup honey
2 large eggs
2 Tbls. pure maple syrup
1Tsp. ground nutmeg
3/4Tsp. vanilla extract
Pierce yams in several places. Microwave until tender, turning once, about 12 minutes. Split potatoes open; scrape flesh into large bowl and mix until smooth. Measure 3 cups mashed potatoes and transfer to another large bowl.
Add all remaining ingredients to 3 cups mashed potatoes; beat filling until blended and smooth.(Can be made one day ahead. Cover and chill.)
Preheat oven 375f. Add filling to pan.
Bake torte until filling is beginning to brown at edges and is just set in center about 1 1/2 hrs. Cool 45 minutes. Cut around pan sides to loosen torte. Remove pan sides.