[SDPhantom]

The DefaultUI already does this.

if self.isHeader then
	self:GetParent():GetParent():OnHeaderButtonClicked(self, self.tradeSkillInfo, button);
else
	if IsModifiedClick() then
		HandleModifiedItemClick(C_TradeSkillUI.GetRecipeLink(self.tradeSkillInfo.recipeID));
	else
		self:GetParent():GetParent():OnRecipeButtonClicked(self, self.tradeSkillInfo, button);
	end
end

Blizzard_TradeSkillRecipeButton.xml:169

This is what calls the function you noted.