01 - Combine milk and lavender buds in a medium saucepan. Heat over medium heat until just simmering. Remove from heat, cover, and let steep for 15 minutes.
02 - Strain the milk through a fine mesh sieve to remove lavender buds, pressing gently to extract maximum flavor. Return the infused milk to the saucepan.
03 - Whisk together egg yolks and sugar in a separate bowl until pale and slightly thickened.
04 - Slowly pour the warm lavender milk into the egg yolk mixture, whisking constantly to prevent curdling.
05 - Pour the mixture back into the saucepan. Cook over low heat, stirring constantly with a wooden spoon, until the custard thickens and coats the back of the spoon (reaching 170°F). Do not let it boil.
06 - Remove from heat. Stir in the heavy cream and vanilla extract. Add a drop of food coloring if desired.
07 - Pour the custard through a fine sieve into a clean bowl. Cool to room temperature, then cover and refrigerate for at least 4 hours or overnight.
08 - Churn the chilled mixture in an ice cream maker according to manufacturer's instructions. Transfer to a lidded container and freeze until firm, about 2–4 hours.
09 - Serve scoops of lavender ice cream garnished with extra lavender buds or edible flowers, if desired.