Prepare your pan by lining an 8-inch square baking dish with parchment paper. Leave some overhang on the sides to act as 'handles' for easy removal.
In a medium saucepan over medium heat, melt the butter.
Continue to simmer, whisking occasionally, until it froths and you see golden-brown flecks appear at the bottom. This is brown butter and adds incredible flavor!
Whisk in the powdered sweetener and vanilla bean seeds.
Continue to cook, whisking constantly, for about 5 minutes until the mixture is smooth and well combined.
Remove the pan from the heat and immediately stir in the chopped almonds, ensuring they are fully coated.
Quickly pour the hot mixture into your prepared pan and spread it into an even layer.
Let it cool completely at room temperature, then transfer to the refrigerator to set firmly, about 15 minutes.
Once chilled and hard, lift the brittle from the pan using the parchment paper handles. Break it into bite-sized pieces and serve.
Store any leftovers in an airtight container in the refrigerator for up to 2 weeks.
Don't walk away from the butter! Brown butter adds a deep, nutty flavor, but it can burn in a matter of seconds. Watch it closely.
Work fast. The brittle mixture begins to harden as soon as it's removed from the heat. Have your prepared pan ready to go before you start.
