Line your baking pan with parchment paper, leaving overhang for easy removal, and preheat the oven to 180°C (350°F).
In a medium saucepan, melt the butter over low heat until it’s just bubbling and fragrant, about 2 minutes. Stir in honey or maple syrup, and cook for another minute to combine.
Remove the saucepan from heat and immediately add the peanut butter, stirring until smooth and gooey—your kitchen will fill with a warm, nutty aroma.
In a large mixing bowl, combine the rolled oats, salt, and vanilla extract, then pour the warm peanut butter mixture over. Mix thoroughly with a spatula until everything is evenly coated and sticky—this is when the mixture starts to come together.
Add the semi-sweet chocolate chips, gently folding them into the mixture to evenly distribute, making sure some chips stay semi-frozen to prevent melting into the dough.
Transfer the mixture to your prepared pan, pressing it down firmly with the back of a spatula or your fingers to create an even, compact layer—this helps ensure chewy, dense bars.
Bake for about 12-15 minutes, until the edges are golden and fragrant. The top may crack slightly—it’s a sign they’re just right.
Remove from the oven and let cool in the pan on a wire rack for at least 20 minutes. The bars will set and develop a glossy, chocolatey sheen.
Once cooled completely, lift the bars out of the pan using the parchment overhang and cut into 8-10 squares with a sharp knife—clean cuts make for pretty pieces.
Serve these chewy bars as a portable snack, enjoying the perfect balance of salty peanut butter, sweet chocolate, and hearty oats with every bite.