Combine all the ingredients in a bowl and whisk to combine. This helps remove some of the air pockets and distributes the flavours evenly.
Pour the mixture into the 470ml Ninja Creami tub - it should reach the fill line or be just below it. Freeze for 16-24 hours with the lid off.
When ready to eat, take the mixture out of the freezer about 5-15 minutes beforehand (less time in summer or a hot kitchen, more time in winter or a cold kitchen).
Process the mixture using the light ice cream function. I generally find I need to process it twice on light ice cream - respin isn't quite enough to achieve the right texture.
Return leftovers to the freezer with the lid on. I find frozen yoghurt gets a freezer taste really easily, so it's important to store the leftovers with the lid on. I recommend re-spinning any leftovers on light ice cream to restore the texture.
Notes
Full fat yoghurt will give you the best texture here. I wouldn't recommend using light yoghurt here.
I find frozen yoghurt more likely to be a little bit icy and have icy edges. I assume this is the lack of fat when compared to a cream based ice cream. You can add 0.5g (heaped 1/8th teaspoon) of xanthan gum to help create more chewy texture to your frozen yoghurt if you have no issues with xanthan gum.
I find yoghurt is more prone to the outside temperature than an ice cream. In the heat, I recommend only leaving it on the bench for about 5 minutes before processing. If you let it sit for too long before processing it, the mixture will be more like a milkshake. Again, I assume this is because it doesn't contain nearly as much fat as a cream based ice cream.