Line a baking sheet with parchment paper and spread chopped roasted almonds evenly in a single layer.

In a medium saucepan over medium heat, combine unsalted butter, granulated sugar, light brown sugar, water, light corn syrup, and fine sea salt. Stir continuously until melted and sugars dissolve, about 3–5 minutes.

Attach a candy thermometer and bring the mixture to a boil, cooking until it reaches 300°F, stirring occasionally, about 10 minutes.

Remove from heat at 300°F and stir in vanilla extract, allowing it to bubble slightly.

Quickly pour the hot toffee mixture over the layer of almonds, spreading evenly with a spatula. Let cool at room temperature for about 30 to 45 minutes.

While cooling, melt the white chocolate melting wafers in a microwave-safe bowl, heating in 30-second increments until smooth.

Once toffee is cool, pour melted white chocolate over it, spreading evenly with a spatula.

Mix granulated sugar and ground cinnamon in a small bowl and sprinkle generously over the melted chocolate.

Allow the chocolate to set completely at room temperature or in the refrigerator for about 30 minutes before cutting into squares.