Microwave Caramel

In high school one of my girlfriends used to make these microwave caramels and bring them to share with everyone. They're easy, delicious and there is just something fun about unwrapping wax paper and sinking your teeth into a gooey caramel, wouldn't you agree?

2 cubes butter
2 1/4 c. brown sugar
1 c. karo syrup
1 can sweet condensed milk
dash of salt
1 tsp. vanilla

Melt butter, blend in sugar, milk, salt & karo syrup. Cover microwave on high for 10-12 minutes. Take out and stir, cook on medium high 16-20 minutes or until candy forms, add vanilla. Pour into greased 8x8 pan. Cool and cut. Wrap in wax paper.