In a large bowl, combine 1/4 cup brown sugar, granulated sugar, and cinnamon.
Cut each biscuit in 4 pieces and add to the bowl. Toss to coat in the cinnamon sugar.
Melt 1/2 a cup of the butter and drizzle it into the bowl. Add the pecans and stir to mix the butter in.
Line a 4-quart slow cooker with parchment paper. Place half the biscuit mixture in the slow cooker.
Melt the remaining 1/2 cup of butter and stir in the remaining 3/4 cup brown sugar. Drizzle half this mixture over the biscuit pieces in the slow cooker.
Top with the remaining biscuit piece mixture and drizzle the remaining butter mixture on top.
Place a double layer of paper towels over the top of the slow cooker and place the lid on. Cook on HIGH for 2 to 3 hours or until set in the middle. Note: the center will stay a little bit gooey.
Let cool in the slow cooker for 10 minutes and then remove and invert onto a serving platter.
To make caramel sauce, heat butter, brown sugar, and heavy cream in a small saucepan until the butter melted. Simmer for 3 to 4 minutes, stirring continuously.
Remove form heat and stir in vanilla, salt, and pecans, Let cool slightly and then pour over monkey bread.