In a large skillet over medium heat, heat the olive oil. Add the garlic and red pepper flakes and cook until just fragrant, 1 minute. Add the anchovies, capers and olives and cook until the anchovies have begun to dissolve in the oil, about 5 minutes. Pour in the wine and the Basic Tomato Sauce and bring to a simmer. Add the fish fillets, making sure they are submerged in the sauce, and gently simmer until the fish is cooked through and the flesh is milky white and slightly flaky, about 10 minutes. Season with salt and pepper, to taste.
Meanwhile, cut each fingerling in half lengthwise and place in a medium bowl. Toss well with salt and pepper. Heat the olive oil in a large skillet over high heat. Add the potatoes, cut side down, and cook until well browned, about 5 minutes.
Serve the potatoes alongside the puttanesca and garnish with basil and freshly ground black pepper.