Add water and sugar to a heat resistant bowl and microwave (600 W) for about 50 seconds to make the syrup (just make sure the sugar melts). Let it sit to cool.
Add cooled syrup from Step 1 to the yogurt. Also pour in lemon juice.
Mix well. Taste test at this point and add more lemon juice as you like (I always add a lot of lemon juice because I like it a bit sour).
Leave it to chill in the freezer for 3 to 4 hours. Take it out to mix several times during that period. And then you're done!
This frozen yogurt can take on many forms. You can mix in jam or fruits (banana, melon, kiwi, canned tangerine, canned pineapple, etc.) (Mix in at Step 3)
Here's a picture of when I mixed in marmalade. It was delicious. You can also use your favorite jam. (Make sure to use less sugar if you add jam)
Here's another example where I added canned tangerines in Step 3. I mashed the tangerines as I mixed it all together. You could also use canned pineapple.
Here's an example of when I used blueberry jam. I made the sauce on top by melting a little bit of jam in hot water. This version tasted great too.
Story Behind this Recipe
My daughter said a friend of hers (a boy) would be coming over, so I tried to be cool and made this frozen yogurt. After eating it the boy gave me a wonderful smile and told me "It was delicious, thank you!", so I got really excited and posted the recipe online.
The important part is making the syrup. The water that's added helps it become icy and crunchy. Also, it's annoying, but remember to take the yogurt out and mix it while it's in the freezer.
If you're going to add jam, then make sure to add less sugar. Same with fruit, adjust the yogurt to how sweet you want it to be. You have to add lemon juice.