Remove wrapping from cheese and place on a microwave-safe serving plate about 1-1/2 inches larger all around than cheese; set aside.
Combine butter and almonds in a 1-cup glass measuring cup. Microwave on high, stirring once, until almonds are toasted, about 3 to 4 minutes, watching carefully. (this can also be done in a small skillet until almonds are toasted.)
Spoon the almond mixture over cheese. Microwave on medium-high (70%) power until cheese is hot throughout, 45 seconds to 1-1/2 minutes. Cheese should ooze out when cut. Serve as a spread for plain crackers.
Note: I wrote this exactly as written in the magazine, but since this recipe is from 1980, microwaves could have had different settings. I microwaved mine on high until the cheese was warmed and oozed out. Serve immediately while cheese is hot and runny.
Recipe by The Culinary Cellar at https://theculinarycellar.com/brie-with-almonds-and-butter-from-1980-vintage-cuisine-magazine/