Roast your beets. Do this by wrapping two or three small, trimmed beets in foil and then placing in a 400 degree F oven for about 45 minutes or until tender. The beets will feel similar to a cooked potato if pierced with a fork. Let them cool and then you can peel them. The peel should just slide right off. Once peeled, slice into 1/4" thick disks. In a small bowl, whisk the vinegar, oil and salt. In a larger bowl, combine the lettuce, pork, oranges, onion, cilantro, and jalapeno. Drizzle with the dressing and then toss to combine. Serve the salad on top of the sliced beets.