Prepare your malanga, taro, or yuca according to the instructions in [recipe:Mashed Malanga]. You will use about 2 cups of broth for this, be sure to save 1/2 cup for the pie filling.
Brown ground beef in a large pan over medium low heat. Drain beef and set aside. Remove excess rendered fat from pan. You want to leave behind about 2 Tbsp to cook your veggies in.
Add your mirepoix, herbs, and salt and pepper to the pan and cook, stirring often, until the carrots have softened. Add garlic and continue to cook another minute or two longer, until garlic is fragrant. Go ahead and start to preheat your oven to 450F. Mine takes about 10 minutes to heat up.
Add bone broth and allow to simmer several minutes. Add ground beef back to the pan and stir everything together well. Let simmer another minute or two then remove pan from heat.
Get a 9"x13" baking dish and add ground beef mixture, spreading evenly.
Using a large spoon or a spatula, carefully cover the top of the meat mixture with your mash. Be sure to spread it evenly.
Bake, uncovered, for about 30 minutes at 450F.
Let rest about 5-10 minutes before serving. This can be a meal in itself, or pair it with your favorite leafy greens as a side.