2bunches of rhubarb, trimmed110 gm (½ cup)raw caster sugar3cardamom pods, bruised2oranges150 gmhoney, plus extra to serve350 gmmascarpone1vanilla bean, scraped seeds only8thick slices of sourdough bread2eggs, lightly beaten with ¼ cup milk60 gmbutter, coarsely chopped
Cut two-thirds of the rhubarb into 2cm pieces, place in a colander, rinse under cold water and shake off excess. Combine in a heavy-based saucepan with sugar and cardamom. Add three pieces of orange rind removed with a peeler and juice of 1½ oranges. Stir over medium heat until sugar dissolves, then simmer until rhubarb is tender and mixture is jammy (about 15 minutes). Remove from heat, discard cardamom and peel, and cool.
Meanwhile, preheat oven to 200C. Cut remaining rhubarb into 5cm pieces and place in a single layer on an oven tray. Drizzle with 50gm honey and squeeze over juice of remaining half orange. Roast until just tender and glazed (about 15 minutes), keep warm.
Combine mascarpone, vanilla seeds and remaining honey in a bowl. Mix until smooth.
Pour egg mixture into a shallow tray and set aside. Spread one side of each bread slice thickly with mascarpone mixture, then with rhubarb jam. Place slices bread-side down into egg mixture and stand until bread absorbs a little of the mixture (about 1 minute). Heat half the butter in a large frying pan over medium until butter foams. Add half the prepared bread, bread-side down, and cook until golden (about 2 minutes). Transfer to a baking paper-lined oven tray. Repeat with remaining bread, then bake until warmed through (about 5 minutes). Serve immediately with roast rhubarb drizzled with extra honey.