There’s no need to wait till Memorial Day. Enjoy all the toast y feels of s’mores in mid-February, no campfire required, by making a few tweaks to a st andard batch of puffed-rice-cereal bars. Cook the marshmallows under the broiler for a minute, so they’re nicely charred, and st ir crushed graham crackers and chopped chocolate in with the cereal. Let cool before slicing into squares or st amping out hearts for Valentine’s Day with a cookie cutter. For the full recipe, see page 97.