In a medium bowl, mix the flour, baking soda, salt, and poppy seeds. Set aside.
2 3/4 cups All-purpose flour, 1 tsp Baking soda, 1 tsp Salt, 1 TBSP Poppy seeds
Using a mixer, beat the butter and sugar on high speed for 2 minutes. It will become pale and fluffy.
1 cup Unsalted butter, 1 1/2 cups White granulated sugar
Add in the lemon zest, egg, and egg yolk and mix on medium speed until combined. Make sure to scrape the bowl using a rubber spatula.
1 Large egg, 2 Large lemon zested, 1 Egg yolk
Add in the dry ingredients and mix on low speed until just combined. This will be a thick dry dough. This helps to prevent spreading from all the moisture the filling provides.
Preheat the oven to 350℉. Line two cookie sheets with parchment paper. Let the dough rest for at least 10 minutes.
Use a large cookie scoop to scoop the dough. While still in the scoop, press your thumb into the center going 2/3rds down. Stuff a frozen cheesecake dollop inside and fold the cookie dough back on top.
Place 6 cookie dough balls per cookie sheet. Bake one sheet at a time. Bake for 13-15 minutes. The edges of the cookie will be lightly golden.
Cool on the hot pan for 4 minutes before transferring to a cooling rack. Cool completely.