ok, I did not quite follow exactly, but i just got inspired by it.
it's from his book Jamie's Dinners ("Tomato Sauce with Portabello Mushrooms and Taleggio" on pg 44 to be exact)
He's written how to make good tomato sauce for pasta or sausages, prawns, anything. 
I bought a bottle of organic tomato sauce (not ketchup ah) from the Australian fair last weekend in BSC. It's made with organic tomatoes, basil, garlic.. and etc. so it's already made-ready, i didnt follow JO's tomato sauce.
Chop garlc and fry them gently in olive oil and oregano. Pour in the sauce and let it simmer for about 1 minute. Add some black pepper.
Pretty simple. Cook pasta according to the label behind the box.. eg 9 minutes. I opted for the Whole Wheat Pasta i bought in CS last week.
Pour the warm tomato sauce into a small baking dish. Place cooked pasta on top, give it a lil stir. Place the portabello mushrooms facing up. Spread some parmesan (i used parmesan instead of taleggio – no idea what's that). Drizzle with olive oil. Scatter some torn breadcrumbs if u have. Bake in oven at 220 C for 15-20 minutes.
the tomato sauce wash garlic-y. the oregano aroma was strong. the parmesan was a bit chewy, maybe mozarella would be nicer ? well, i would try Taleggio if i know where to buy it.
ah.. satistying brunch 
