Step 1. Preheat the oven to 350°F (175°C). Line two light colored baking sheets with parchment paper or silicone baking mats and set aside.
Step 2. In a medium bowl, whisk together the all purpose flour, baking soda and salt until evenly combined. This helps distribute the leavening and salt throughout the dough.
Step 3. In a large mixing bowl, beat the softened butter, light brown sugar and granulated sugar with an electric mixer on medium speed for 1 to 2 minutes, until the mixture looks light, creamy and slightly paler in color. Scrape down the sides of the bowl once to make sure everything is combined.
Step 4. Add the eggs one at a time, mixing on low speed just until each egg is incorporated. Mix in the vanilla extract. The mixture should look smooth and glossy.
Step 5. Add the flour mixture to the bowl in two additions. Mix on low speed after each addition until you no longer see dry streaks of flour. Stop as soon as the dough comes together to keep your heart shaped chocolate chip cookies soft and tender.
Step 6. Use a spatula to fold in the semisweet chocolate chips until they are evenly distributed. If you plan to add chopped chocolate on top, keep that separate for now.
Step 7. Scoop about 2 tablespoons of dough for each cookie and place the portions on the prepared baking sheets, leaving about 3 inches between scoops to allow room for spreading. For even results, use a cookie scoop so the cookies are all the same size.
Step 8. Gently press a few pieces of chopped chocolate and some Valentine sprinkles onto the top of each mound of dough. This makes the tops of your easy heart shaped cookies look festive and full of chocolate.
Step 9. Bake one tray at a time for 9 to 11 minutes, until the edges of the cookies look set and lightly golden but the centers still look soft and a bit pale. The cookies will continue to firm up on the hot tray, so avoid baking until they are deeply browned.
Step 10. As soon as the cookies come out of the oven, work quickly while they are still hot and soft. Press a heart shaped cookie cutter straight down into each cookie. Wiggle gently, then remove the excess cookie around the cutter, leaving a clean heart shape behind. Repeat with each cookie.
Step 11. Use a small offset spatula or thin spatula to transfer the cut heart cookies to a wire rack. Let the heart shaped chocolate chip cookies cool until set. If you like, sprinkle a tiny pinch of flaky sea salt on top of the warm cookies for a sweet and salty finish.
Step 12. Serve the cookies slightly warm or at room temperature. They are perfect for Valentine baking for kids, school parties or romantic dessert ideas for couples, and they stay soft and chewy for several days when stored in an airtight container.