Line a rimmed baking sheet with parchment paper. In a bowl (or in the yogurt container itself) mix the yogurt, honey, and vanilla. Pour on to the prepared baking sheet and spread in an even layer about 1/4-inch thick. Sprinkle with the granola, peanuts, cranberries, M&Ms, and sea salt, if using. Transfer the baking sheet to the freezer and freeze until firm, about 2 hours. Break into shards. Frozen yogurt bark will keep for about a week, stored in an airtight container in the freezer.