In a large saucepan over medium-low heat, heat the butter and olive oil. Add the leeks, onion and garlic and cook until translucent and soft.
Add the potatoes, chicken stock and season with salt and pepper. Bring to a boil and then simmer for 15 minutes or until the potatoes are very soft.
Use a hand-held blender or food processor to puree the soup until smooth and creamy.
Add the cooking cream and bring to a low simmer for a further 2-3 minutes or until heated through.
Meanwhile cook the streaky bacon in a frying pan until crispy and set aside.
Serve the soup with the crispy bacon and hot buttered bread.
Thermomix Method
Place the chopped leeks and onion into the Thermomix bowl and chop for 5 seconds on Speed 6. Scrape down the sides of the bowl.
Add the butter, olive oil and minced garlic and saute for 5 minutes, 100 degrees, Speed 1.
Add the potatoes and cook for 5 minutes, 100 degrees, Speed 1.
Add the chicken stock liquid, salt and pepper and cook for 20 minutes on 100 degrees, Speed 2, (with the MC removed but the rice bowl or splatter guard sitting on top to avoid any splatters). Allow the soup to cool slightly.NOTE: Ensure the ingredients do NOT go past the full/max line. Use less liquid stock if need be.
Allow the soup to cool slightly. Ensure the rice basket or splatter guard is placed over the top of the MC hole. Very slowly increase to Speed 6. Puree for 30 seconds.
Add the cooking cream and heat for a further 3 minutes, 100 degrees, Speed 2.
Meanwhile cook the streaky bacon in a frying pan until crispy (optional).
Pour the soup into bowls and serve with crispy bacon on top.
Notes
RECIPE NOTES & TIPS
Clean your leeks well - dirt often hides between layers; slice lengthwise and rinse thoroughly.
Cut potatoes small - smaller chunks cook faster and blend more evenly.
Don't over-blend - stop as soon as it's smooth to avoid a gluey texture.
Adjust consistency - if too thick, stir in extra stock or milk after blending.
Cream substitute - for a lighter option, swap cream for milk or leave it out entirely.
Make it vegetarian - skip the bacon and use vegetable stock.
Storage - store in the fridge for up to 3 days in an airtight container.
Freezing - freeze for up to 3 months; thaw overnight in the fridge and reheat gently on the stove or in the microwave.
Thermomix Specific Tips
Never exceed the MAX line - if you find that you are getting close to the MAX line, simply omit some of the liquid chicken stock.
Use the splatter guard or rice basket to avoid splatters when cooking - leave the MC off (measuring cup) and place the splatter guard (or use the rice basket in earlier models) over the top to prevent any splatters.
Allow the soup to cool slightly before pureeing - it is dangerous to use the Thermomix at high speeds to puree while the soup is still hot. Allow it to cool slightly and then use the splatter guard/rice basket to prevent splatters.