In small saucepan heat milk to a simmer- remove & carefully pour over chocolate chips.
Whisk until all chocolate chips are melted.
Whisk in sugar & coffee extract until blended.
At this point your liquid should be cool enough to add your eggs without scrambling them.
Whisk until the eggs are completely combined.
Pour over your crust that should have come out from baking just moments before you finished the chocolate liquid mixture.
Bake 30 minutes or until the edges have risen slightly higher than the center & center is just set. (mine had some spots that rose into large bubbles- they flattened once it cooled)
After removing from the oven- sprinkle with toffee bits & remaining 1/2 cup of chocolate chips.
Set IN PAN on wire rack to cool 15 minutes.
Move to refrigerator for a minimum of 2 hours to fully set.
Once set- pull up on parchment to remove from pan & cut into squares.
Store in air tight container in the refrigerator.