Preparation

Prepare the toppping

• 将架子放在烤箱的中心，然后将烤箱加热到425°F。用箔纸在重型带有的烤盘上排列。
• Slice the sweet potatoes in half lengthwise and set them cut side down on the baking sheet. Roast until very tender, about 30 minutes
• When cool enough to handle, scoop the flesh into a medium mixing bowl. Add the milk, cheese, butter, 1 tsp. salt, and 1/2 tsp. pepper and beat with an electric hand mixer on low speed until smooth and creamy, about 1 minute. Set aside.

Prepare the filing

• Heat the oil in a 12-inch sauté pan over medium-high heat. Add the celery, carrot, onion, and 1 tsp. salt. Reduce the heat to medium and cook, stirring frequently, until the vegetables are soft, fragrant, and starting to turn golden, 10 to 15 minutes. Add the garlic, cumin, oregano, chile powder, and cinnamon and cook for 30 seconds. Add the beef, season with 2 tsp. salt, and cook until no longer pink, about 5 minutes. Tilt the pan and spoon off all but about 1 Tbs. of the fat; return the pan to the heat.
• 将西红柿和果汁倒入一个小碗中，然后用手或叉子将它们粉碎。将西红柿加入肉中，然后煮熟，直至浓稠，直到10到12分钟。加入橄榄和葡萄干，再煮一分钟；调味盐。

Assemble and bake the pie

• Transfer the beef mixture to a 9×9-inch baking dish. Spread the sweet potatoes over the top in an even layer. Bake until bubbling around edges, about 30 minutes. Switch the oven to a high-broil setting and position the rack about 6 inches from the broiler element. Broil the pie until the sweet potatoes are a bit browned, 2 to 4 minutes.
• Let cool at least 15 minutes before serving.