Preheat the oven to 180C, Line a 24 hole mini-muffin pan with mini liners or grease it well with butter.
Finely chop the dried lavender flowers and mix them with orange zest and 1 tsp sugar using your fingertips. This helps in releasing aromas and also helps to reduce orange zest becoming lumpy.
Melt together butter, dark chocolate and brown sugar using a double boiler or in a microwave oven for 1-2 mins, stirring every 30 seconds so that it doesn't lump.
Stir the vanilla, egg and zest-lavender sugar into the chocolate mixture. When the mixture is blended, add the flour and stir only till it is incorporated, do not overmix. You should have a smooth, glossy yet thick batter.
Spoon about 1.5 tbsp of batter in each of the prepared muffin tin and bake for about 10-12 minutes till the toothpick comes out clean. Set aside for 10 minutes to cool.
In the meanwhile, melt chopped white chocolate, cream and sea salt together over a double boiler or in microwave for 30 seconds. Do not overmelt the white chocolate. After 30 mins and a little whisking the chocolate should be ready.
Once the buttons are cool, using a fork or piping bag spread the white chocolate on the buttons in zig zag fashion, you can even dip the buttons in the chocolate but I find it too sweet then.
The buttons are ready to be served.