Preheat oven to 400℉. Line an 12x17 inch rimmed baking sheet with parchment paper.
Sprinkle the baking sheet with cheese so that there is a thin even layer of cheese. Next, line up the onion ring slices so that they are not totally overlapping but right next to one another. Lightly brush tops of onion rings with olive oil (or spray). Then season with salt, garlic powder and paprika generously. Bake for 18-20 minutes (rotating the pan halfway through) or until golden brown and crispy.
Ground Meat:
While the onion rings are baking in the oven, heat the olive oil in a skillet over medium-high heat. Once the pan is hot, add in the ground meat and use a wooden spoon to break up the meat. Next, add in the seasonings and stir to coat. Then add in the broth and cover for 10 minutes. Uncover and stir the mixture. Remove pan from burner but keep the pan covered.
Assembly:
Once the onion rings are done allow them to cool for just two minutes (don't wait too long because the onion sheet will harden and you won't be able to roll it). Flip the onion sheet over. Layer the ham slices and cheese slices evenly. Spread out the ground beef evenly and lastly place on the pickles. Start rolling tightly from the short side of the rectangle, upwards towards the other short side. Reposition the roll on the baking sheet so that the seam side is down and tucked under the roll. Bake for 7-10 minutes. Slice and serve warm.