Preheat the oven to 425 degrees F. Combine the turnip and carrot in a large microwave-safe bowl with 1 tablespoon water. Cover with plastic wrap and microwave until just softened, 3 to 5 minutes. Drain.
Add the beef curry and Worcestershire sauce to the vegetables and stir to combine; season with salt and pepper. Unroll the pie dough and cut each round in half. Spoon one-quarter of the filling on one side of each semicircle and fold in half to form a wedge. Crimp the edges with a fork to seal. Transfer to a baking sheet; cut two or three slits in the tops. Bake until deep golden brown, about 20 minutes.
Meanwhile, combine the shallot with 2 tablespoons each vinegar and water in a small bowl; let stand 10 minutes, then drain. Whisk the remaining 1 tablespoon vinegar, the olive oil and mustard in a large bowl until smooth; season with salt and pepper. Add the arugula, parsley and shallot and toss. Serve with the handpies and more mustard for dipping.
Toss the beef and potatoes with the curry powder, 1 teaspoon cumin, 1 tablespoon ginger, the garlic, 1 teaspoon salt and a few grinds of pepper in a 6-quart slow cooker. Crumble 1/2 slice of naan into small pieces over the beef and potatoes, then pour in the tomatoes. Cover and cook on low, 7 hours.
Uncover and skim off any fat from the top of the mixture. Stir well to combine, then let stand 10 minutes. Meanwhile, combine the cilantro, pickled jalapenos and brine, 1/4 cup water and the remaining 1/4 teaspoon cumin and 1 tablespoon ginger in a food processor. Pulse until combined; season with salt and pepper.
Stir 3 tablespoons of the cilantro puree into the slow cooker; season with salt and pepper. Serve the curry with the naan; top with the remaining cilantro puree.
Recipe courtesy of Food Network Magazine