The avocado pile in the produce section can be intimidating. For avocado newbies, it can be tricky to determine whether your selection is a “dud” or a “stud.”

Full of healthy omega 3 fats, vitamin B6, folic acid, and potassium, avocados are one of the healthiest foods you can add to your diet. They’ve been shown to help maintain a healthy heart, manage blood pressure, lower cholesterol and prevent multiple diseases.

Master the avocado stack with this helpful guide. It can get you closer to reaping the benefits of adding avocados to your diet.

How to Pick an Avocado

The way to identify a ripe avocado is by color and touch. Unripe avocados are light green and very firm. Ripe avocados are a dark green, almost purple color and soft to the touch. If it’s mushy or bruised, it’s overripe. Put it back on the stack.

Ripe avocados should be eaten within one to two days, so base your selection on when you plan to eat it. If you think it may be a few days, select a firm green ones and allow it to ripen naturally in your kitchen. This will take about four to five days at room temperature.

How to Slice an Avocado

Because their skin is soft, avocados can be dangerous to cut open. Place the ripe avocado on a cutting board and cut it in half lengthwise. Do not hold the fruit in your hand while cutting. Once it’s opened up, remove the pit with a spoon before removing the skin. The skin should come off easily when you peel it with your fingers. (If the avocado is hard to cut or peel, it may not be ripe enough to eat.) Once the skin is off, you can slice or dice the fruit any way you like, depending on how you plan to use it.

How to Serve an Avocado

Not only are avocados good for you, they are extremely versatile. Here are some of my favorite ways to enjoy avocados:

• Mashed with salt, pepper, and lime juice and served with pita or carrots
• Sliced as a topping for turkey or chicken sandwiches, a great alternative to dressing or other condiments
• Mashed into tuna salad with lemon juice, salt and pepper; the creaminess is comparable to mayo
• Served with eggs as a heart-healthy breakfast.
• Enjoyed as a snack drizzled with balsamic vinegar

Unopened avocados will keep at room temperature. To prolong their shelf life, place them in the produce drawer in your fridge. The cold air stops them from ripening, so refrigerate only the ones that are ready to eat.

Sometimes you only need a small portion of the avocado for a recipe or snack. But if you’ve ever placed the unused half in the fridge, you’ve probably gone back the next day to find a mushy brown mess. Because of all their omega-3 fatty acids, avocados are sensitive to light, air and heat. They easily oxidize when exposed, becoming brown and breaking down. To keep an opened avocados longer, limit its cut surface and exposure. First squirt it with lemon or lime juice and sprinkle a little bit of salt. Then press a piece of plastic wrap over the cut surface and stick it in the refrigerator.