How to Make It
In a large saucepan, cook 1 tablespoon of the butter over moderate heat until it sizzles. Add the cinnamon stick, mussels and white wine, cover and steam until the mussels open, about 2 minutes. Pour the mussels into a large strainer set over a bowl and let cool.
Remove the mussels from their shells and place in a small bowl. Season with pepper and the lemon juice.
Wipe out the saucepan. Add 1 tablespoon of the butter, the chiles and half of the basil and parsley and cook over moderate heat for 1 minute. Add the garlic, tomato paste and the reserved mussel cooking liquid and boil until the sauce has reduced to 1 cup. Remove from the heat and add the mussels.
Dice the remaining 2 tablespoons of butter. Scatter the butter and the feta over the mussels and bring almost to a boil over moderate heat, swirling the pan to melt the butter and feta. Season with salt and pepper. Garnish with the remaining herbs and serve.