Line a 20cm (8-inch) square baking pan with parchment paper, leaving overhang for easy removal.
Place the butter in a medium saucepan over low heat and gently melt, stirring occasionally until just melted and fragrant, about 2 minutes.
Add the caramel bits to the melted butter, stirring constantly. Continue to stir for 3–4 minutes until the mixture becomes smooth, shiny, and slightly bubbling.
Pour in the sweetened condensed milk and stir thoroughly for another 2–3 minutes until the mixture thickens slightly and develops a golden hue, filling your kitchen with a sweet, buttery aroma.
Remove from heat and stir in the vanilla extract and a pinch of sea salt, mixing until well combined and fragrant.
Pour the warm caramel mixture into your prepared pan and use a spatula to spread it evenly, smoothing the surface for a glossy finish.
Refrigerate the pan for at least 2 hours, or until the caramel is firm enough to cut into small squares.
Lift the set caramel slab using the parchment overhang and cut into small squares with a sharp knife. Dip the knife in warm water if sticking occurs for cleaner cuts.
Arrange the caramel bites on a plate or store in an airtight container in the fridge. Let sit at room temperature for about 10 minutes before enjoying for soft, chewy perfection.
