1) Heat the griddle to high.
2) Place a few large cazuelas or a large high-sided saute pan on the grates of the griddle. Add the butter, pepper, salt, lime juice, hot sauce, Worcestershire and thyme and cook until the butter has melted and the mixture begins to simmer.
3) While the butter mixture is melting, toss the prawns with the oil and place on the griddle in an even layer. Griddle for 20 to 30 seconds per side then transfer to the butter mixture, stir to combine and cook until the shrimp are just cooked through, 4 to 5 minutes. Remove from the heat and stir in the parsley.
4) While prawns are cooking, split bread in half, sprinkle with olive oil and salt and pepper, and place on griddle, cut side down, for 1 to 2 minutes until toasted.
5) Serve shrimp with the grilled bread.