Pan size matters: The bars will be slightly thinner in a 9x9 pan and thicker in an 8x8 pan.
Crumb texture: Make sure your cracker crumbs are finely crushed (like a coarse sand texture) so the base holds together well and isn’t crumbly.
Melting chocolate: Heat in 20 second bursts to avoid scorching as the chocolate can seize quickly if overheated.
Clean slices: For clean, sharp cuts, be sure to chill completely and wipe your knife between slices if necessary.