Step 1

Heat the oil and butter in a large saucepan over medium heat. Add the onion and thyme and cook, stirring occasionally, for 3 mins or until the onion softens slightly. Cover and cook, stirring occasionally, for 10 mins or until the onion is soft and light golden.

Step 2

Add the flour and cook, stirring, for 1 min or until the mixture is grainy. Add wine, if using, and cook, stirring, for 1 min or until well combined. Add the stock, mustard and 1 cup (250ml) water. Bring to a simmer and cook for 10 mins or until onion is very soft and the soup thickens slightly. Remove and discard the thyme. Season.

Step 3

Spread blue cheese over the toasts. Ladle soup among serving bowls and top with toasts. Season to serve. Serve with chopped chives and thyme sprigs