Toast the nuts in a large, dry skillet over low heat, stirring frequently, until golden, about 5 minutes. Remove the nuts. Cut the bacon into 1/2-inch pieces and add to the skillet. Cook over medium heat until crisp. Remove the bacon with a slotted spoon and drain on paper towels. Whisk the oil, mustard, lemon juice, sugar, salt, and pepper in a medium bowl. Tear the frisee into small pieces and place in a serving bowl. Add the bacon, nuts, and goat cheese. Toss the salad with the dressing.
Note: It's worth spending more for frisée, because it doesn't wilt easily. But you can also mix it with less expensive curly endive or chicory. To serve 30 people, double this recipe, but set aside half the dressing and greens for late guests.