Cookie cake with secret filling


Slice of cookie cake with marshmallow filling in gooey strandsCookie cake table set up, paired with mango panna cotta

If you love chewy, gooey cookies with a rich caramel flavor, this recipe can quickly become your favorite. I use it for cookie cakes, cookie bars, or as classic chocolate chip cookies. With a little decoration (like frosting, sprinkles, or candies) it can even double as a birthday cake.

What makes this recipe special is simple : its rich caramel flavor and tenderness. Once baked, the cookies have a soft center with golden edges, and stay soft for a few days.

Some things to note : 

  • Brown sugar adds molasses flavor and moisture. This makes the cookies chewy, their toasty color and gives them a distinctive caramel taste.
  • Gentle mixing keeps cookies thick and tender. Overmixing builds gluten, which makes them spread (melt when baking) and hard.
  • Letting the dough rest overnight hydrates the flour, firms the butter, and develops richer flavors.

I’ve played around with fillings too, from chocolate hazelnut cream and marshmallows to pistachio cream or even speculoos spread with chocolate bars. The base recipe stays the same, and you get endless variations.
Here' the dough recipe :
100 g butter
60 g of brown sugar
80 g of granulated sugar
2 teaspoons of vanilla
1 egg
160 g flour + 50 g if necessary
1/2 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon salt
1 cup chocolate chips (you can mix milk and white / peanut butter / butterscotch)
1/2 cup nuts (optional)
6-8 marshmallows or chocolate caramel bars or cream filling (hazelnut or pistachio or almond cream).  

Method

  1. In a bowl, cream the butter with both sugars. Add the egg and vanilla.

  2. Fold in flour, baking powder, baking soda, and salt. Mix only until combined.

  3. Fold in chocolate chips and nuts if using.

  4. Refrigerate dough for at least 2 hours, ideally overnight.

For classic cookies

  1. Scoop portions of dough onto a baking sheet lined with parchment. I usually make 2-1/2 inch round disks about 1 inch thick.

  2. Bake at 180°C / 350°F for 10–12 minutes. The centers should look/feel slightly soft.

    (You can also sandwich cookies by filling with chocolate hazelnut cream or a marshmallow inside) 

Layering dough, chocolate marshmallows in between
A layer of cookie dough topped with some
chocolate-covered marshmallow bears

For a cookie cake

  1. Spread half the dough into a 23 cm (9-inch) round, square, or rectangular pan.
  2. Press edges 1 cm higher than the center to hold the filling.

  3. Add your filling of choice: marshmallows, slices of candy bars, peanut butter cups, almond cream, speculoos spread, or a mix (I've tried them all, there are some great combinations I'll let you discover on your own)

  4. Top with the remaining dough.

  5. Bake at 180°C / 350°F for 20–25 minutes until edges are golden and the center is set but soft.

Tips

  • Let the cake cool before cutting. Marshmallows are hot and gooey out of the oven, for the good of all mankind!

  • Try flavor twists: hazelnut cream with marshmallows (my boss once said I was asking for a raise with this one), pistachio cream with chocolate bits for a nutty and less sweet option (but color oh so surprising), or speculoos spread with sliced chocolate bars for a bold cinnamon mix.

Enjoy warm or cooled, with friends or as a treat for yourself !

Slices of cookie cake with pistachio and marshmallow filling
A rectangular sheet cake filled with pistachio cream and marshmallows.
Dessert buffet with cookie cake, plum crumble and creme brulée
Side note : I didn't use dark brown sugar for this version, but a lighter sugar and the dough is lighter in color.

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Some useful links for baking equipment or similar objects in photos :

9" springform pan

10" square springform pan