Cut the orange slice, rind included, into four pieces and place in a food processor or blender with the whole cranberries. Mix until evenly chopped, then add 1/3 cup sugar. Stir until blended; set aside.
With a mixer, cream butter and sugar. Add salt, orange juice concentrate, vanilla, eggs, and mashed cooked sweet potatoes, beating all until thoroughly blended; set aside.
In a small bowl, combine flour, brown sugar, and butter, pressing and stirring with a fork until butter is evenly distributed. Stir in pecans; set aside.
Pour half of the sweet potatoe mixture into a buttered 2 1/2-3 qt casserole dish. Spread cranberry mixture evenly over top, then cover with remaining sweet potato mixture. Bake for 10 minutes at 350 degrees before sprinkling with brown sugar-pecan combination. Return to oven and bake for an additional 45 minutes. Remove and cool for 5-10 minutes