Pierce the sweet potatoes six to seven times each with a knife and microwave, skin on, on high power for 6-8 minutes or until a knife in the center goes cleanly through. When cool enough to handle, peel and cut into ¼-th inch thick slices.
In a skillet, heat the oil. Add the leeks or shallots and garlic and saute until they are soft and start to brown, about five minutes.
Add the meatless beef and cook, stirring and breaking up any big lumps, for five minutes.
Add the tomatoes, smoked paprika and chili powder. Mix well and cook a couple more minutes until tomatoes begin to break down.
Add the black beans (drain before using). Add half to one cup of water (I use half because I like this chili really thick) and stir it all well. Add salt if needed. Bring to a boil, let it simmer on low heat for five minutes, then turn off the heat.
While the chili is cooking, preheat the oven to 425 degrees.
Mix the panko breadcrumbs in a small bowl with sage, salt, ground black pepper, cheddar cheese shreds and a teaspoon of oil. You can skip the cheddar cheese but it's really nice and kids, especially, love it.
After the chili is cooked, transfer it to a baking dish if not using an oven-safe skillet.
Layer the sliced sweet potatoes on top of the chili. Sprinkle the breadcrumb mixture on top of the sweet potatoes.
Bake 20 minutes or until the breadcrumbs are golden and the chili is bubbling. Let stand five to 10 minutes before serving.