Field Salad With Tangerines, Roasted Beets, And Feta

Ingredients:2 beets (about 1/2 pound)1/2 teaspoon grated tangerine rind6 cups gourmet salad greens1 cup tangerine sections (about 3 tangerines)1/4 cup (1 ounce) crumbled feta or blue cheese1/4 cup fresh tangerine juice1/4 teaspoon black pepper1 tablespoon fresh lemon juice2 teaspoons extra-virgin olive oil1/8 teaspoon salt1/8 teaspoon Dijon mustard