In a large bowl, whisk together the tahini, chia seeds, matcha powder and kosher salt. Set this aside.
In a small pot or saucepan, add the sugar, water and vanilla extract. Put this on medium heat and stir to combine. Let the sugar start to bubble slightly, stirring often.
Let the sugar mixture get to 245°F and then immediately pour it into the tahini mixture.
Quickly stir the sugar mixture and tahini together, the tahini will immediately begin to thicken and seize up.
Pour the halva mixture into two parchment lined 8"x5" loaf pans, pouring the mixture until it is about 1.5" high. Tap on the counter to smooth out the top, and then move the pans to the fridge to chill for 30 minutes to an hour.
While the halva is setting, melt the chocolate and coconut oil together until smooth. You can do this in the microwave in 30 second increments.
When the halva is set, slice each pan into 12 pieces. Drizzle the chocolate mixture on top of each piece, and sprinkle with edible flowers. Move back to the fridge to set a second time.
Let the halva set another 30 minutes in the fridge, and then serve!
Store the halva in the fridge and grab a piece whenever you'd like one. These will keep for up to two weeks.