Preheat the oven to 350°F (175°C). Line an 8-inch square baking pan with parchment paper, leaving an overhang on two sides for easy removal.

In a large bowl, add 2 eggs, 1 cup peanut butter, and 1/3 cup pure maple syrup. Add 1 tsp vanilla extract if using. If the peanut butter is firm, microwave it for 20–30 seconds to soften. Mix until smooth and well combined.

Add 1 1/2 cups rolled oats, 1/4 tsp baking soda, 1/2 tsp ground cinnamon (if using), and 1/2 tsp sea salt to the bowl. Stir until a thick, evenly combined dough forms.

Fold in 1 cup chocolate chips if using.

Transfer the dough to the prepared pan and press it into an even layer, smoothing the top. If desired, sprinkle extra chocolate chips or a small pinch of sea salt on top.

Bake on the center rack for 20–25 minutes, or until the bars are set and the edges are slightly golden brown.

Remove from the oven and let the bars cool in the pan for at least 15 minutes. Use the parchment overhang to lift the bars from the pan, then slice and serve.