In a large bowl, whisk oats, flour, brown sugar, cinnamon, and salt until well blended. Reserve 2 cups for topping, then press remaining mixture firmly into a parchment-lined 8×8-inch pan.

Bake the pressed oat base at 350°F until edges turn golden, about 10 minutes.

In a small saucepan over medium heat, combine fresh cranberries, maple syrup, and honey. Cook until cranberries soften and mixture thickens, about 5 minutes, stirring occasionally, then remove from heat and stir in vanilla extract.

In a medium bowl, toss reserved oat mixture with melted butter until crumbly. Sprinkle generously over the filling.

Bake at 350°F for 15–20 minutes or until the topping is golden brown and filling bubbles at the edges.

Let the bars cool completely, about 30–45 minutes, then lift from the pan using parchment edges and slice into squares.