Best healthy burger strategies

Burger season is here!  
How can you enjoy a good burger without feeling the bulge later?  

Homemade burger facts 
195 calories - 4 oz. homemade burger patty of 85% lean meat.
120 calories - average bun. 
  20 calories - 1 Tbsp. ketchup.
  70 calories - 1 slice of cheese (approx.). 
    5 calories - 1 tsp. Dijon mustard. 
    5 calories - 1 slice of tomato.
    3 calories - 1 slice of romaine lettuce.
Total 418 calories (average).

Not terrible, but let’s admit that this is a very conservative burger. Many burgers can be upwards of 700 calories.
This means:
47% of the calories come from the meat.
29% of the calories come from the bun.
25% of the calories come from the condiments.

What can be done to make this better?
Use Leaner Meat
There is a fine line between having enough fat so your burger has good flavor and having too little so it ends up a dry, flavorless meat blob. I mix my 85% lean ground beef with a little 90% lean.  You can also cut your burger portion down to 3 oz. That will save you about 40–50 calories.
Hollow out your bun, only eat the bottom or lose the bun entirely
The calories in a bun coming from white flour are considered “empty calories.” Hollow out the top of the bun and you can reduce the amount of bread by 25% and remove approximately 60 calories.
You can also lose the top of the bun. That will remove almost 70 calories. Or you can substitute the bun for 2 crisp romaine lettuce leaves. They add crunch and you can remove about 115 calories from your burger.
Consider different toppings
Swap the cheese out for fresh avocado slices. They add a creamy texture and tons of flavor.
Try a fresh salsa as a topping, or roasted red peppers and caramelized onions with Siracha for a little kick.  
Choose healthy sides
You’ve made good choices so far. Be careful what you have with your burger. Chips and potato salad can pack big calorie punches, so lean (no pun intended) towards fresh fruit or raw veggies or just take your time and enjoy each bite of your wonderful burger. Relish in the tastes, smells and great company of the season.