Keep the Greek-style yogurt and 3/4 cup of plain yogurt in the fridge until the moment they’re needed in order to keep them cold. Add 1/4 cup of plain yogurt and sprinkle 3 tsp of unflavoured gelatin over the top in a small pot. Warm the mixture over low heat while stirring constantly with a spoon or whisk, until the gelatin has completely dissolved. You should only warm the yogurt just enough to melt the gelatin but never boil it. Add 3/4 cup of cold plain yogurt in a large bowl and pour the yogurt/gelatin-mixture over it while whisking with your other hand (you can use a hand-held mixer for this). The mixture should be smooth, thick but lump-free. Add the honey and whisk to combine, then finally the Greek-style yogurt. Whisk again until lump-free.
Pour the mixture into a shallow baking-dish and freeze until hard (at least several hours). Remove the hard-frozen yogurt and cut into small chunks with a knife (this is why it’s better to have it as a shallow slab for easy cutting). Add the chunks into a food-processor, then pulse. At first they will tumble, then they will break down into small pieces, then into breadcrumb-like consistency. And it may seem that they’ll never come together as a creamy mixture, but they will. Once they reach the breadcrumb-consistency, keep the food-processor running on high until eventually smooth and creamy. There. Magic soft-serve frozen yogurt.