Line an 8x8-inch baking pan with parchment paper, leaving a 2-inch overhang on two sides for easy removal later. Lightly spray with nonstick cooking spray.

Combine the white chocolate chips, sweetened condensed milk, and butter in a large microwave-safe bowl. Microwave on medium power in 30-second intervals, stirring thoroughly after each burst, until completely melted and smooth — about 2-3 minutes total.

Remove from microwave and immediately stir in the vanilla extract and sea salt until evenly combined. The mixture should be glossy and pourable.

Reserve 2 tablespoons of crushed freeze-dried strawberries for topping. Gently fold the remaining strawberries into the white chocolate mixture, stirring just until swirled throughout but not fully mixed — you want pretty pink streaks.

Pour the fudge into the prepared pan and spread evenly with a spatula. Tap the pan gently on the counter 2-3 times to release any air bubbles.

Sprinkle the reserved crushed strawberries over the top, pressing them lightly into the surface so they adhere.

Refrigerate uncovered for at least 2.5 to 3 hours, or until completely firm to the touch.

Use the parchment paper handles to lift the fudge out of the pan. Place on a cutting board and let sit at room temperature for 10 minutes, then use a sharp knife to cut into 1-inch squares, wiping the blade clean between cuts for neat edges.