In a large stock pot, heat the olive oil. When the oil is hot, add the chorizo and onions. Saute the mixture for 2 minutes. Add the garlic and potatoes and cook for 2 minutes, stirring occasionally. Add the stock and kale and bring the liquid up to a boil. Stir in the bay leaves, thyme and crushed red pepper. Season with salt and pepper. Reduce the heat to a simmer and cook until the potatoes are fork tender, about 30 minutes. Remove from the heat and skim off any fat. Stir in the parsley. Ladle the soup into shallow bowls and garnish with the fresh mint. Serve the soup with crusty bread.