In her new book, Dessert for Two (Countryman Press, Feb.), Christina Lane (the blogger behind a site of the same name), scales down well-loved desserts into small-batch, two-serving recipes. With Valentine's Day just around the corner, we asked Lane to share a recipe—baked in two mason jar lids—from the book. It's the perfect ending to the year's most romantic meal.

Chocolate Caramel Mason Jar Lid Tarts

Maybe there are a lot of mason jar recipes in this book, but I just can’t help it. I think they’re adorable, and perfect for portion control. Ever since I noticed they mimic little tart pans with removable bottoms, I’ve been baking up all sorts of treats in them. Play around with the fillings in this recipe — substitute a different type of chocolate if you like, use jam instead of caramel, or try cookies instead of graham crackers. The possibilities are endless and delicious!

Yield: 4 individual tarts

4 graham cracker sheets (106 grams), broken into pieces

2 teaspoons granulated sugar

2 ½ tablespoons (37.5 grams) unsalted butter, melted

2 cups (380 grams) milk chocolate chips

¼ cup (60 mL) heavy whipping cream

2 to 3 teaspoons Salted Caramel Sauce (below)

PREHEAT THE OVEN TO 350°F. Place four pint-sized mason jar rings on a small baking sheet. Place the lids with the rubber part facing down.

In a food processor, combine the graham crackers and sugar. Pulse for about 30 seconds, or until finely ground. Stream in the melted butter and continue to pulse. The mixture should appear like wet sand, and it should slightly clump together when squeezed in your hand. If you overmix, it will turn into dough —not good.

Divide the graham cracker crumbs between the mason jar lids. Use a shot glass to pack in the crumbs and push them up the sides of the ring.

Bake for 10 minutes. Let cool completely on a cooling rack.

Now we’re going to melt the chocolate. It can be finicky, so this is the way I do it: Bring 1 cup of water to a boil in a small saucepan. Make sure you have a glass bowl that fits over the pan without touching the water. Place the chocolate chips and cream in the glass bowl, and have it ready next to the stove. Once the water boils, turn off the heat and place the bowl of chocolate and cream over the pan. Stir, stir, stir until the chocolate melts. You may have to turn the heat back on to boil the water again, but I find that if I’m patiently daydreaming while stirring the chocolate, it all melts just fine.

Pour the melted chocolate into the tart shells.

Tap the lids gently to get rid of any air bubbles.

Let sit for 10 minutes.

Dot drops of caramel sauce onto the surface of the chocolate, and after a few seconds, run a toothpick or knife through the chocolate to swirl it together.

I recommend refrigerating the tarts for a few hours to set the chocolate. However, before serving, let them come back to room temperature — the chocolate is too hard when cold.

The tarts will keep for up to 3 days refrigerated.

FOR THE SALTED CARAMEL SAUCE

⅓ cup (65 grams) granulated sugar

2 tablespoons (30 grams)

unsalted butter

3 tablespoons (45 mL)

heavy whipping cream

¼ teaspoon kosher salt