Soak the roll in water, then squeeze it out thoroughly. Finely dice the onions. Combine the minced meat, squeezed roll (or breadcrumbs), diced onions, and herbs in a large bowl. Season with salt and pepper. Stir in the vegetable stock until you have a uniform batter.
Grease a deep baking sheet and spread the minced meat batter evenly on it. Drain the pineapple slices thoroughly and arrange them on one half of the meat. Place 1 teaspoon of jam in the center of each pineapple slice. Arrange the bacon strips on the other half of the meat.
Roast in the oven at 170 °C (338 °F) for 1 hour. After roasting, strain the pan juices through a sieve into a saucepan. Skim off excess fat and bind the liquid with the sauce thickener to thicken the gravy.