Heat a skillet on medium-high heat and add the Italian sausage. Cook until browned and no longer pink, breaking it up with a spoon as it cooks. Remove to a paper towel to drain.
Using a serrated knife slice the Hawaiian rolls in half horizontally so you have a top layer and a bottom layer. Place the bottom layer into a baking sheet or 9x13 baking pan.
Add 1/2 of the shredded cheese onto the bottom layer followed by 1/2 of the pepperoni slices.
Add the cooked Italian sausage on top. Followed by the remaining shredded cheese.
Add the sliced olives evenly over the sausage and cheese. Place the top layer of slider buns on top.
In a small bowl, add the butter, garlic, Italian seasoning, parsley, and 1 tablespoon of Parmesan cheese and mix until combined.
Brush the butter mixture over the top of the slider buns. Cover with aluminium foil and bake 20-25 minutes.
Remove from the oven and sprinkle the remaining grated Parmesan on top, and serve with a side of pizza sauce.
Notes
Prep these sliders ahead of time. Assemble pizza sliders and place them into the refrigerator, brush the butter mixture on top and bake.