Christmas Caramels

My husband's maternal great-grandmother made these by the basketful at Christmastime. 

In a heavy saucepan, combine: 
2 c sugar
1-1/2 c light corn syrup
2 sticks butter (unsalted)
1/2 pint heavy cream
1 can (12 oz) evaporated milk

Cook and stir over medium heat to firm ball stage (use a candy thermometer for this) -- 245 F, about 12 to 15 minutes. Remove from heat and stir in 1 tsp vanilla. Pour into a buttered 9x9 pan. Cool and cut into squares. Wrap each square in wax paper.