How would i have the color of fire in a brick change rapidly?

Id like to make it so when you touch the brick, the color of the fire changes. Currently this is the script.

local brick = Workspace.Part

function onTouch(part)

	brick.Fire.Enabled = true
	wait(3)
	brick.Fire.Enabled = false

end


brick.Touched:connect(onTouch)

Now I want the color of the fire to change while it is shown. Help?

BrickColor.random()