(Notes from my sister) Gramma said do not try to make a double recipe, make only one at a time.
The mixture should be thick and shiny after adding the butter. If it's grainy, you have burned the chocolate, and it won't be smooth on setting.
INGREDIENTS
4 oz semisweet chocolate
3 Tbs milk
1/4 c unsalted butter
1 large egg yolk
cocoa
DIRECTIONS
Melt chocolate with milk. [ probably in a double boiler ]
Add butter. Stir until butter just melts.
Set aside to cool.
When cool, add egg yolk and blend.
Refrigerate until chocolate is firm enough to shape into small balls.
Dip fingers into cocoa and roll into balls, then into cocoa powder.
Store in a cool place - not fridge.