1. Wash the kale and pat it dry. Gently tear the leafy portion away from the thick stems. Place the kale leaves in a steamer and steam for 5 minutes or until wilted. Place the wilted kale in a food processor and puree the kale. Drain any excess liquid and set aside the kale. You should have about 1 cup of kale.
2. Meanwhile, in a small mixing bowl, combine the flour, cocoa powder, and salt. Mix until thoroughly combined.
3. In the top of a large double boiler, melt the butter, the chocolate chips, and the dark chocolate together, stirring until evenly melted and smooth. You can also melt in microwave for 30 seconds, stir, and repeat until the chocolate is mostly melted and only a few tiny pieces remain. Remove from heat and let it sit until it cools to room temperature. 
4. Add the eggs, kale, sugars, and vanilla and mix with the chocolate mixture until combined. Gently fold in the flour mixture until just barely combined, taking care not to over-mix.
5. Prepare a 13″x 9″ pan by greasing it with butter and then lining it with parchment paper. Carefully pour the brownie batter into the pan. Bake at 350 degrees for 35 minutes, or until a toothpick comes out clean. Yield: 24 brownies.

Note: As soon as possible after they come out of the oven, carefully lift the brownies up (by holding on to the parchment paper) and out of the pan (if they sit in the hot pan they may continue to “cook” and may get dry). Allow the brownies to cool while sitting on the parchment paper before cutting them.