Avoid bitter tomato sauce with this dead-simple tip. Serious Eats / Diana Chistruga You've spent hours simmering tomato sauce made with ripe, juicy tomatoes from the farmers market, only to find it acrid and bitter. Was your olive oil rancid? Were the tomatoes spoiled or of low quality? Or was it simply bad luck? Chances are, you've overcooked or burned your garlic. It's a mistake that even the most experienced home cooks can make: You turn your back for a minute, and before you know it, your garlic is dark brown and past the point of no return. As our editorial director, Daniel , has written previously , garlic can smell and taste burned "even before it has fully turned into blackened bits of carbon." Because garlic contains a high concentration of naturally occurring sugars, it tends to burn easily.…