In a shallow baking dish melt the 2 tablespoons butter on high 30 seconds.
Add 1/2 cup almonds and heat, uncovered, on high 3 to 4 minutes, or until almonds are toasted.
Stir each minute of heating.
In a deep, 3-quart casserole combine sugar, the 1/2 cup butter and evaporated milk.
Microwave, uncovered, on medium for 18 to 20 minutes, or until mixture reaches 234°F with candy thermometer.
Add broken pieces of white chocolate and miniature marshmallows.
Beat until melted.
Add toasted almonds and vanilla.
Beat until candy thickens.
Pour candy into a buttered, shallow baking dish.
Cool before cutting into squares.