No-Bake Honey Nut Cheerios Snack Bars

creamy unsalted butter (half of one stick)

honey (light-colored corn syrup may be substituted and will keep the bars firmer at room temp than using honey)

light brown sugar, packed

vanilla extract

Honey Nut Cheerios (or similar storebrand cereal; plain Cheerios may be substituted for a less sweet bar)

raisins, optional (1 cup  honey-roasted peanuts, 1 cup chopped almonds, or 1 cup trail mix may be substituted)

about 1/2 cup chocolate-covered sunflower seeds, optional (I used Trader Joe’s)

sea salt or Kosher salt for sprinkling, optional