In a small bowl, combine the yeast with the warm milk, sugar, and oil and set aside for 5 mins until the yeast dissolves. in a large bowl, combine the flour and salt. While mixing, pour in the milk mixture. make sure all the yeast comes along with it.

Transfer the dough to a lightly floured counter and knead the dough until you have a nice supple smooth ball that is no longer sticky. you might have to add a little more flour.

With an electric mixer, beat the butter until creamy. Add the garlic, mint, and pepper and beat well. you can add some salt if you wish, but remember that the feta is salty, so be judicious. Cover and set aside.

Blanch the radicchio in boiling water for 2 seconds and drain well in a sieve. Chop it even more finely.

Preheat the oven to 350 F (180 C). Oil a 9 inch round pan.

Knead the dough briefly, then dust the counter with flour, shape the dough into a rectangle, and roll it out about 16 x 20 inches.

Reserve about 1/4 of the garlic butter, and spread the remaining garlic butter over the dough. Sprinkle with the feta and the radicchio. Roll up the dough from the long side and wrap it in plastic wrap. Place the roll in the freezer for about 15 min to stiffen; cutting will be easier that way. Melt the reserved garlic butter in a saucepan and remove from the heat.

Cut the roll into 1 - 1 and 1/4 inch rounds. Arrange them close together in the baking dish; its fine if they touch each other. Brush the tops with the melted garlic butter and let stand for another 15 min. Bake for about 30 mins, until golden brown.