Make a pot of coffee using whatever brewing method you prefer.
Measure 2 oz of Spiced rum with the jigger. Toss the spiced rum in the mug.
Measure 1 oz of heavy cream with the jigger. Toss the heavy cream in the mug.
Measure 4 - 5 oz of coffee with the jigger. Toss the coffee in the mug.Note: as an alternative to measuring with the jigger, you can just pour the coffee into the mug and top it off