Using a sharp knife, cut the candy bars into 1/2 to 1-inch chunks.
You should have about 1 cup. Place the chunks in a bowl; cover and freeze.
Whisk the egg in a mixing bowl until light and fluffy, 1 to 2 minutes.
Whisk in the sugar, a little at a time, then continue to whisk until
completely blended, about 1 minute more. Pour in the cream, milk
and vanilla extract and whisk to blend. Transfer the mixture to
ice cream maker and freeze following manufacturer's instructions.
After the ice cream stiffens (about 2 minutes before it is done)
add the candy, then continue freezing until the ice cream is ready.
Makes a generous 1 quart
Coffee Heath Bar Crunch:
Omit vanilla extract and substitute 3 tablespoons good quality freeze-dried
coffee. Add 2 tablespoons coffee with the cream and milk, and add
the remaining 1 tablespoon coffee along with the candy (after the
ice cream stiffens).