Heat half the oil in a large non-stick frying pan or barbecue plate over high heat. Add mushrooms and garlic and cook, turning occasionally for 5 minutes until light golden and tender. Remove to a plate, lined with paper towel. Cover to keep warm.
Add bacon to the hot pan or barbecue and cook for 1 minute each side or until golden. Transfer to plate with the mushrooms.
Drizzle the remaining oil over both sides of steak and season with salt and pepper. Cook steaks, 2 at a time, for 2 minutes each side for medium or until cooked to your liking.
Place 4 slices toast on clean board. Combine the mayonnaise and chili jam. Use half to spread over the toast. Top with rocket, steak, mushrooms, cheese, bacon and beetroot. Spread remaining mayonnaise mixture on remaining toast. Sandwich together and skewer with toothpicks or cocktail sticks. Cut in half and serve with hot chips if desired.