This is from an Irish hotel (The Cliff House in Waterford) we visited once - the chef had a cook-book out, so I bought one.
You could prep the rhubarb at home and then it's just a matter of chucking the pastry on and into the oven about 15 mins or so before you want to eat it.
Ingredients: 1 sheet of puff pastry 5 medium sized pears, peeled, cored & quartered 200g sugar mixed with seeds of 1/2 a vanilla pod, and 1/2tsp each of ground nutmeg & cardamom (probably would double this if using rhubarb) 50g butter 70ml water zest of 1 lemon (you won't need that with the rhubarb!) Non-stick, oven-proof 24cm frying pan
Pre-heat oven to 175C Add the sugar mix and water to the pan Dissolve on a medium heat and then let it come to the point of caramelisation Add the butter and the pears and soften them slowly on a low heat, turning so they are cooked on both sides Finish with pears round side down and evenly arranges Cover with the pastry and press and mould it tight Bake until crust is light brown and crisp Remove from oven and place serving dish on top of the pan/pie Turn it out Cut and serve with vanilla ice cream and a glass of Baileys.