- ½ cup (1 stick) unsalted butter, softened
- ½ cup sugar
- 1 teaspoon vanilla paste or vanilla extract
- 1 large egg yolk
- 1⅛ cup (1 cup plus 2 tablespoons) all-purpose flour
- ½ teaspoon salt
- about ½ cup jam (your choice of flavor)
- scant ½ cup chocolate chips
- 12-15 full sized marshmallows, cut in half or thirds horizontally
Set rack in the middle of the oven, and heat oven to 350˚F. Line an 8×8 pan with parchment paper, leaving some flaps on each side. Set aside. Note: if you have an 8×8 square removable-bottom pan, this is the time to use it!
Cut marshmallows into thirds or halves (obviously, thicker pieces make a thicker marshmallow layer: please yourself in this) and reserve.
Using an electric mixer, beat the butter and sugar together until pale and fluffy. Stop the mixer, scrape down the bowl, then add in vanilla paste (or extract) and egg yolk. Beat again, until well mixed. Stop mixer again, add flour and salt, and beat on low speed until completely incorporated.
Scrape batter into prepared pan. With clean wet fingers (wet fingers keeps the dough from sticking to them) press the dough across the bottom of the pan. Work quickly; try to make the dough as even as you can.
Bake crust 20-24 min, until golden brown around the edges but still puffy and soft in the center. Remove crust from the oven and let rest about 20 min.
Now you’ll need to move the crust out of the 8×8 pan and onto an ungreased, unlined cookie sheet. Use the flaps to carefully lift the crust out, then run a knife or spatula under the crust, and carefully slide it out onto the unlined baking sheet.
If you will use chocolate, sprinkle the crust with some good quality chocolate chips, and return to the oven for 3-4 minutes. Remove from oven and spread the chocolate evenly and gently. A small offset spatula is the perfect tool for this. Let the crust rest about 10 more minutes.
Substitutes for chocolate in this layer: Nutella, butterscotch chips (melt as above), peanut butter, almond butter.
next layer: the jam
Add a layer of fruit preserves. I had some black raspberry jam to use. Apricot or raspberry or cherry would be great with chocolate – this is where your imagination comes in. At any rate, you’ll use 1/4 to 1/2 c of the preserves, and spread them thinly.
and top with marshmallow
Now arrange the sliced marshmallows on top of the jam. Note: next time I make these, I’m going to see about using a layer of marshmallow fluff. Return the pan to the oven for 4-5 minutes, to soften the marshmallows. Remove from the oven, and turn the oven to use the broiler setting.
Use the back of a spoon (or your trusty offset spatula) to gently press and smoosh the top of each marshmallow. Once they are all smashed, return the pan to the broiler. Watch the tops carefully! Toast the marshmallows to your desired shade; remember that they brown very quickly.
Remove the toasted cookie bars from the oven. You’re finally finished! Allow to rest at least 10 minutes before slicing, and use a wet knife, wiping the blade with a wet cloth after each slice.
store in an airtight tin
The cookies will keep, well wrapped, at room temperature for up to 4 days. However, today, within three hours, the pan was mostly devoured by the three of us. You have been warned!
These cookies are inspired by and adapted from Joy the Baker – and they remain a favorite way to use up open jars of jam.