Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius).

In a large mixing bowl, beat the margarine or oil, sugar, vanilla, and eggs; lower speed and add cocoa, flour, baking powder, and salt, beating until well combined.

Spread batter onto a parchment-lined cookie sheet and bake for 30 minutes. Remove from oven and allow to cool. Spread caramel cream over the cooled crust and sprinkle with 1/2 cup of chopped nuts. Place in freezer.

Combine all ingredients, except for the pecans, beating together until the mixture thickens and reaches a creamy consistency.

Pour in the ground nuts and beat a few seconds longer, until nuts are fully incorporated into the mixture.

Spread ice cream over the caramel and pecan layer and return the pan to the freezer.

Place chopped chocolate into a small bowl.

Heat pareve whipping cream in a small pot. Once it reaches a simmer, pour it over the chocolate in the bowl. Allow the mixture to sit for a few minutes without stirring so the chocolate melts. Stir mixture until it begins to thicken and achieve a shiny appearance.

Add vanilla and stir to incorporate.

Pour ganache over ice cream and drizzle with a few tablespoonfuls of caramel cream. (I squeezed the cream through a piping bag and it drizzled beautifully.)

Sprinkle with remaining 1/4 cup chopped pecans and return to freezer until ready to serve.