Toss fresh cherries with 1 tbsp. sugar and set aside in refrigerator.
Preheat oven to 350°. Butter a 9- by 13-in. pan. In a medium saucepan, melt butter and chocolate over very low heat, stirring constantly with a heatproof rubber spatula, until just melted. Do not let simmer or boil. Remove from heat and let cool slightly, about 5 minutes.
In a large bowl, whisk together eggs, 2 cups sugar, vanilla, and salt. Slowly pour chocolate-butter mixture into egg mixture, whisking constantly. With a rubber spatula, thoroughly but gently fold in flour. Add dried cherries and chocolate chips and stir just until combined.
Spread batter evenly into baking pan and bake 35 to 40 minutes, or until brownies are firm, beginning to pull away from sides of pan, and a toothpick inserted near the middle of the pan (2 in. from the edge) emerges with only a few crumbs clinging to it (try to avoid inserting a toothpick into chocolate chips).
Let brownies cool completely, then cut into 24 to 30 1-in. chunks (you will have about a half-pan of brownies left over). Put 3 brownie chunks in each of 8 to 10 sundae dishes or shallow bowls, add a generous scoop of ice cream to each, and top with fudge sauce and fresh cherries.
Nutritional analysis per 3-in. brownie: Calories 372 (47% from fat); Protein 3g; Fat 19g (sat 11g); Carb 50g; Fiber 4g; Sodium 159mg; Chol 87mg.
Note: Nutritional analysis is per serving of sundae.