To reduce the bitterness you may want to blanch or boil the bitter melon for 2-3 minutes. There is no need to peel as the skin is edible.
The most important thing about this dish is not to over cook the bitter melon. You don't want to lose the crunch. You want to make sure to control the heat.
Slice the bitter melon lengthwise, remove seeds and pith then cut into smaller slices.
Since bitter melon is a more dense vegetable it will take longer to cook than other more delicate vegetables.
Add the oil and melons to your already heated pan. Stir until the melon is completely covered. If the melon seems dry don't be afraid to drizzle a bit more oil.
Make sure the melon is spread evenly so it cooks with the heat and not with the steam. Stir every minute to ensure even cooking of each piece. Don't stir too often though or the melon will start to cook in the steam rather than the heat. The steam is what makes them mushy, and you don't want that.
After 5 minutes add the garlic, let it cook in the oil for about 15 seconds. I like to create a little space in the center to do this, then I mix everything together again.
At the end of the cooking time, approx 10 minutes, you will add the fish sauce. Depending on your taste buds you may wish to add a little more fish sauce.
To prep you will want to remove the seeds, I cut the ends off then slice down the middle lengthwise. Once opened you can scoop out the seeds easily enough.
From that point on you can juice it, blanch it or cut and cook however you like.
For treatment of diabetes and liver support, it is recommended to consume one small, unripe, raw melon or between 50-100 ml of fresh juice per day. You may want to divide the juice into two or three doses rather than all at once.