Summertime is burger time. While I am a fan of the classic cheeseburger with perfectly melted sharp cheddar cheese, crisp lettuce and tomato on a nicely buttered and grilled bun, there is something to be said for the switch up we are seeing at burger joints all over the place and their gourmet takes on our old favorite.

In the spirit of keeping everything on the grill this week, I've created a recipe with super fresh ingredients all packed with extra flavor via some smoky charring.

The key to a great burger meat mixture relies on two elements: the right amount of fat content in the ground beef, and the right amount of salt in the mixture. I'd recommend no more than 89 percent lean beef. The fat content here adds to the juiciness and tenderness of the burger, as well as helping to hold the meat together when formed into patties. Additionally, about 1 teaspoon of salt per the 2 pounds of ground beef is the target amount to season and also help the protein bind and not fall apart on your grill.

Before you grill the pineapple, be sure to pat the pieces dry of excess moisture. Also, make sure to rub or toss everything gently in olive oil and season with a sprinkle of salt before grilling. The onions might be a little tricky, but be careful when slicing the rings to keep all the ring pieces together so that you can grill one flat layer of onion at a time to avoid them falling down into the flames of the grill.

Mozzarella Cheeseburgers with Grilled Pineapple Salsa

For burgers:

2 lbs. 83% lean ground beef

1 clove garlic

1 tsp. kosher salt

1/4 tsp. fresh ground pepper

1 tsp. Worcestershire sauce

Mozzarella cheese slices

1. In a large mixing bowl, add the ground beef, salt, pepper and Worcestershire sauce. Using a fine grater or zester, grate the garlic clove over the top.

2. Using your hands, thoroughly mix the ingredients until all are incorporated. Allow the mixture to rest for 15-20 minutes before use.

3. Divide the beef mixture into 6 even portions, and form patties. Grill on medium heat for about 6 minutes on each side, or to desired doneness. Add the cheese atop the burger during the last 2 or 3 minutes of cooking to allow to melt.

4. Top the burgers with Grilled Pineapple Salsa and serve on a buttered and toasted bun.

For Salsa:

6 slices fresh pineapple, 1/4 inch thick

1 large jalapeno, halved & cored

1 small red onion, sliced into rings (keep sections together)

Olive oil, as needed

1 tsp. champagne vinegar

1. Gently rub the pineapple and veggies with olive oil, and sprinkle with a little bit of salt. Be careful to keep the onion rings together in their layers so they can be cooked flat on the grill in even slices. Cook over medium heat (about 375 degrees F), about 5-7 minutes on each side, until tender with light char marks. Allow to cool for a few minutes.

2. Roughly chop the pineapple and veggies, and combine in a small mixing bowl with champagne vinegar and salt & pepper as desired.

Jessica Roy is a specialty chef and caterer, food writer and chef instructor, and owner of Shiso Kitchen in Somerville, where she teaches classes. Follow her at http://blogs.lowellsun.com/yourpersonalchef.