Pick bunches of acacia flowers with scissors or small pruning shears. Choose freshly opened flowers and avoid faded flowers that will have less flavour. Remove the insects that may be lodged in them.
Heat the cream in a saucepan over low heat until it boils.
Remove the pan and put the acacia flower clusters in it. Let infuse 30 minutes.
Then filter the cream, add honey (or sugar) and agar agar powder (if you do not have a precise scale to weigh the 2 grams, put 1 / 2 teaspoon) and return to heat.
Mix regularly and bring to a boil. Boil for 30 seconds, whisking well.
Pour the cream into ramekins or small bowls, leave to cool and then put in the refrigerator for at least 3 to 4 hours.
Serve with hazelnuts or crushed pistachios on top.