Preheat the oven to 425 degrees F. Wrap the sweet potatoes in foil and bake until fork-tender, about 45 minutes.
Meanwhile, make the dressing: In a large bowl, whisk together the tangerine zest and juice, olive oil, and crushed red pepper. Season to taste with salt and pepper, then stir in the dates.
Cut the dandelion greens crosswise so they are the length of the sweet potatoes (you want them to fit nicely on top).
When the sweet potatoes are cool enough to handle, slice them open in half lengthwise, then break up the flesh with a fork. Toss the dandelion greens in the dressing, taste and adjust seasoning, then place on top of the sweet potato halves. Drizzle any extra dressing over the sweet potatoes.