For the Cake
Preheat oven to 350.

Butter two 9-inch round cake pans. Line bottoms of pans with parchment paper. In a heavy 1-2 quart pan over low heat, stir brown sugar, butter, and 3 tablespoons cream until melted and blended, about 5 minutes. Pour half the brown sugar mixture into each of the cake pans. Sprinkle cup pecans evenly into pans.

In a bowl, with a spoon, beat eggs, granulated sugar, and oil until well blended. Stir in pumpkin and vanilla. In an another bowl, whisk together flour, baking powder, spices, baking soda, and salt. Whisk dry ingredients into pumpkin mixture until well blended. Pour half the batter into each of the pans; smooth top.

Bake 30-35 minutes. Let cool in pans on racks about 5 minutes, then invert onto racks and remove pans and paper. Let cool completely, about 1 1/2 hours. Refrigerate until ready to frost.

For the Frosting
Using an electric mixer, beat the cream cheese, vanilla, and sugar until light and creamy. Beat in 1/4 cup whipping cream until smooth (scrape and stir with spatula as necessary). Add the rest of the cream and beat until it has the consistency of whipped cream (don’t overmix). Spread half of the frosting between the two cake layers then spread the rest over the top layer.