Place leek and EVOO into the Thermomix bowl and chop 3 sec/speed 5.
Sauté 5 min/Varoma/speed 2.
Add remaining ingredients and cook 14 min/100°C /speed 2.
Blend 1 min/speed 5–6, bringing speed up slowly to avoid spatter.
Serve hot with a dollop of crème fraiche or mascarpone cheese and freshly cracked black pepper.