These lemon poppy seed Rice Krispie treats take the classic, chewy no-bake marshmallow cereal bars you grew up with and give them a bright, citrusy upgrade. Fresh lemon zest and juice balance the sweetness, while poppy seeds add a subtle crunch.
Lightly grease a 9x13-inch pan and line it with parchment paper, leaving a slight overhang for easy removal. Set aside.
Add the butter and marshmallows (leaving out about 1 cup) to a large pot set over medium-low heat. Stir with a rubber spatula until the butter is melted and the marshmallows are completely smooth. Stir constantly so the marshmallows don’t burn or stick to the bottom.
140 grams unsalted butter, 566 grams marshmallows
Reduce the heat to low and stir in the vanilla, salt, lemon juice, and lemon zest. Remove the pot from the heat once everything is smooth.
½ teaspoon vanilla extract, ⅛ teaspoon salt, 2 tablespoons lemon zest, 3 tablespoons lemon juice
In a large bowl, whisk together the Rice Krispies cereal and poppy seeds. You can also pour them directly into the pot with the marshmallow mixture for easier clean up.
Pour the warm marshmallow mixture over the cereal, then gently fold until evenly coated. Add the extra mini marshmallows and fold just until combined so you still have pockets of whole marshmallows throughout.
Transfer the mixture to the pan and gently press it into an even layer using a greased spatula or your hands. Avoid pressing too firmly, or the treats can turn dense.
Cover with plastic wrap and refrigerate for at least 30 minutes or until the treats are set. Garnish with more lemon zest, slice, and enjoy!
Notes
Storage: Store the Rice Krispie Treats in an airtight container at room temperature for up to 1 week. Place sheets of wax paper between each layer so they don't stick together.Freezing: Place the treats in an airtight container or freezer bag with pieces of wax paper between each so they don't stick together. Freeze for up to 3 months, and let them thaw overnight in the refrigerator before serving.