1. Heat oven to 350 degrees . Butter and flour a 9 x 12 x 11/2-inch baking pan.
2. Melt butter, 8 oz of the chocolate chips and the unsweetened chocolate together in a medium bowl set over simmering water. Allow to cool for 15 minutes. In a large bowl, stir (do not beat) together eggs, coffee, vanilla and sugar. Stir chocolate mixture into egg mixture and allow to cool to room temperature.
3. In a medium bowl, sift together 1/2 cup of the flour, the baking powder and salt and add to chocolate mixture. Toss remaining 6 oz chocolate chips and remaining 2 tbsp flour in a medium bowl and add to chocolate mixture. Spread evenly in prepared pan.
4. Bake at 350 degrees for 35 minutes, until a toothpick comes out clean. Don't overbake!
5. As soon as brownies are out of oven, place jar of caramel sauce without the lid in a microwave and heat just until it's pourable. Stir until smooth. Drizzle caramel evenly over hot brownies and sprinkle with sea salt. Cool completely and cut into 12 bars.
6. Note: It is very important to allow the batter to cool before adding the chocolate chips, or the chips will melt and ruin the brownies.