Heat the heavy cream in a saucepan over low heat, stirring occasionally, until it reduces by about 10%. For a deeper colour, add a pinch of turmeric. Do not skip the reduction or the dessert will not set properly.
Separate the dandelion petals from the green parts while the cream reduces. Discard all green parts to avoid bitterness.
Halve the lemons lengthwise, squeeze and reserve about 30 ml of juice, then scoop out the pulp with a small teaspoon to create clean shells. Place on a tray and stabilise with jar lids or a muffin tin.
Stir the lemon zest, honey and reserved lemon juice into the reduced cream. Leave for ten minutes to infuse, then pour the warm mixture into a blender.
Add the dandelion petals and blend until only small flecks remain and the cream turns yellow. Blend while still warm.
Pour the mixture into the lemon shells, filling almost to the top.
Refrigerate for at least 3 hours or overnight until fully set. Enjoy!