Combine chocolate morsels, brown sugar, butter, light corn syrup, coffee powder, ground red pepper, and salt in a heavy saucepan; cook over medium heat, stirring constantly until mixture comes to a boil. Remove from heat and stir in vanilla and baking soda.
Distribute popcorn and nuts evenly onto 2 lightly greased sheet pans. Pour chocolate mixture evenly over popcorn and nuts, stirring well with a lightly greased spatula.
Bake at 250F degrees for 1 hour, stirring every 15 minutes. Spread onto wax paper to cool, breaking apart large clumps as mixture cools. Store in airtight containers.