Heat oven to 375*.
Trim and cut rhubarb into 3/4" long pieces, place in a shallow ovenproof dish and pour the sugar over the rhubarb and toss it all together so the sugar's well dispersed. Cover with foil and bake about 45 min or until tender. When you remove the rhubarb, slip a baking sheet in the oven. When rhubarb is cool, strain and reserve juice.
Meanwhile, make the pastry. Using a food processor, mix the dry ingredients, then add butter and cheese and pulse to make a crumbly mixture. Bind with the cream, pulsing sparingly. Let pastry rest in the refridgerator at least 20 min before lining your tart pan. After you've rolled the pastry out between plastic wrap and lined the pan with it, put it back in the refriderator for another 20 minute
Remove from refridgerator and line with foil. Fill pastry shell with dry or baking beans and put on the sheet in the oven for 15 minute.
Gingerly remove beans and foil, keeping in mind their heat, and cook a further 5 min or until it's turning golden brown and is cooked through. Leave to coolon a wire rack.
When you want to assemble the tart (you cando the steps above a good couple days in advance, though keep cooked and colled flan case in an airtight container), reduce about 6 tbsp of the juice to a syrup by boiling it robustly in a small saucepan. Don't leave the pan unattended, though, as the juices will become thickly syrupy in a matter of minutes.
Now for the filling: using a whis, soften the cream cheese, then add the cream, whipping until it has mixed well and thickened slightly. Take care not to overbeat - this must be volumptuous and undulating. Add the sugar and muscat or rum, stir to a soft marscapone consistency, then fill the pastry shell with it. Top with the strained rhubarb pieces, then drizzle over your puce-pink glaze.