Fill the sink with water and salt and put your flowers in. Salt will make the bugs run for their lives (if there are any in there) and water will make the flowers open more easily.
Remove the flowers from the zucchinis very carefully. Use your hands, or a knife to be more sure.
Open the flowers (again very carefully) and remove the stamen. Take care not to tear the flower.
Wash the flowers under running water and strain them on a towel.
Take a flower, open it and put inside a stick of feta and a spearmint leaf.
Twist the petals to close the flower. Put them all in a plate and place them in the fridge until it's time to fry them.
Make the batterput all ingredients in a bowl and mix until you get a nice smooth batter. If you are not going to do the frying immediately, place it in the fridge until then.
The flowers should be served hot, so fry them just before you want to serve them. When it is time, put the oil in a pan, and fry them in medium-hot temperature, for about 3 minutes, turning them until they get golden brown all over.
You can use your fork to flatten the flowers a bit (while frying). They will fry quicker this way.
When they are golden brown all over, put them on a paper towel to absorb the extra oil and serve hot.
