Preheat the oven to 325. Line a 15-by-10-inch rimmed baking sheet with foil and coat with cooking spray.
Mix the oats, peanuts, raisins, seeds, cinnamon, condensed milk and butter in a bowl. Spread evenly on the baking sheet and bake until golden, about 45 minutes. Cool slightly, then lift off the baking sheet using the foil and invert onto a cutting board. Peel off the foil and cut into bars. Wrap individually in plastic wrap.