Cheese Tartlets

Directions

1. For jam: In a small saucepan, melt butter over medium-high heat. Add onion and jalapeño; cook, stirring occasionally, until tender and lightly browned, about 5 minutes. Stir in tomato, sugars, vinegar, 1 teaspoon (3 grams) salt, red pepper, and black pepper; bring to a boil. Reduce heat to low, and simmer, stirring and mashing tomatoes every 5 minutes, until thickened, 30 to 40 minutes. Stir in remaining ¼ teaspoon salt. Let cool completely. Refrigerate in an airtight container for up to 2 weeks. Let come to room temperature before using.
2. Lightly spray 14 (¾-inch-tall) 2½-inch round fluted tartlet pans with baking spray with flour; place prepared pans on a parchment paper-lined baking sheet.
3. For crust: In the bowl of a stand mixer fitted with the paddle attachment, beat butter at medium speed until creamy, about 1 minute. Add Parmesan, shredded mozzarella, egg yolk, rosemary, salt, and pepper, beating until combined, stopping to scrape bottom and sides of bowl. With mixer on low speed, gradually add flour, beating until a smooth dough forms and is no longer crumbly, 1 to 2 minutes.
4. Using a 1½-tablespoon spring-loaded scoop, scoop dough (about 28 grams each) and press into bottom and up sides of prepared tartlet pans. Cover with plastic wrap, and refrigerate for 20 minutes.
5. Preheat oven to 350°F (180°C).
6. Bake until edges are lightly browned, about 20 minutes. Gently press down center of crusts. Fill each crust with about 1 tablespoon (15 grams) tomato jam; top with torn mozzarella. Bake until jam is warm and cheese is melty, 8 to 12 minutes more. Best served immediately.

Pro Tip: If you don’t have mini tartlet pans, you can also use a muffin pan. Fill mini muffin cups with 1 tablespoon (16 grams) tartlet crust dough and 1½ teaspoons (8 grams) jam, or fill regular muffin cups with 2 tablespoons (41 grams) dough and 2 tablespoons (30 grams) jam.