Preheat oven to 350°F and line baking sheets with parchment paper.
Using an electric mixer on medium speed, beat the softened butter and sugars together, about 2 minutes. Add the peanut butter, eggs and vanilla extract, increase the mixer speed to medium-high, and beat until the mixture lightens and begins to thicken, about 1 minute. Scrape down the sides and bottom of the bowl as needed.
With the mixer on low speed, slowly mix in the flour and baking soda into the wet ingredients until just combined.
Scoop out 2 tbsp-sized portions and gently roll into a ball with your hands. Place 3 inches apart on the baking sheet. Use a fork to make a criss-cross indent on top of each. They should be about ½ inch thick.
Add about 1 teaspoon of jam on top of each cookie, being careful to not let it slide off the edge.
Bake for 12-14 minutes. You want the edges to be golden brown. Allow the cookies to cool for 5 minutes on baking sheet before transferring to cooling rack.
Notes
Use room temperature ingredients. You want your eggs to be the same temperature as everything else so it easily combines.
Measure the flour by weight so you get the exact amount needed.
Use a cookie scoop for consistent cookie size, ensuring even baking.
Make sure the jam stays on the cookie dough before baking to prevent it from falling off and potentially burning. You could also make a small well in the center if you are concerned.