In a small pan over low heat, slowly cook the onion in 1 tbsp of the olive oil, stirring occasionally, until it becomes golden brown and caramelised ~ around 15 to 20 minutes. Remove from heat and set aside.
Place a large saucepan over medium heat. Add the olive oil, cardamon, cumin, cloves and cinnamon stick and cook for about a minute, stirring continuously (it will come together into a sticky paste) until fragrant. Add the garlic and cook for 30 seconds more.
Add a tablespoon of water to help lift any spices stuck to the bottom of the pan before adding the rice. Stir to coat the rice evenly in the oil and spice mixture.
Add the vegetable stock and bring to the boil. Cover and reduce to a gentle simmer and allow the rice to cook â€“ about 20 â€“ 30 minutes depending on the rice you are using. Once cooked, stir in the cilantro, currants and pine nuts and â€“ if the rice seems a bit dry and gluggy, the sour cream.
Preheat your oven to 200Â°C/ 390Â°F.
Slice the banana peppers in half, remove the seeds and ribs, and arrange on a lined baking sheet. Spoon the rice mixture into the peppers, cover with foil and bake in the preheated oven for 20 â€“ 30 minutes or until the peppers are cooked and soft.
Remove the foil and sprinkle the feta over the peppers and bake for another 10 minutes or until the feta has melted. Serve.