Combine both chips and peanut butter in a heatproof bowl (preferably with a spout), and set aside.
Combine milk and cream in a small saucepan and heat over medium-low heat, whisking frequently. (The faster you whisk, the foamier the milk will be.)
When the milk looks like it's about to boil, remove from heat and pour into bowl over the chips and peanut butter.
Let sit about 1 minute, then whisk until completely smooth.
Pour into a mug and enjoy!