Preheat grill to medium high heat. Spray an aluminum tin or your favorite barbecue tin with cooking spray. Set aside.
Clean your pumpkin and dry thoroughly. Cut the top of the pumpkin, including the stem, off the very top.
Cut the pumpkin in half vertically. Using a grapefruit spoon, scoop out the seeds and stringy pulp. Discard the strings and save the seeds if you want to roast them later for a snack.
Peel the outer layer of skin with a potato peeler.
Cut the pumpkin meat into bite-sized pieces. Toss with olive oil and lemon pepper and place into the prepared pan.
Place the pan in the middle of the grill and roast until beginning to brown. Using a metal spatula, turn the pieces of pumpkin to brown the other sides. This process will take about 15 minutes all together, depending upon the heat of your grill.
Alternatively, you can roast the pumpkin in the oven at a high temp of 425℉ to 450℉ to achieve the same effect of browning and slightly caramelizing the pumpkin bites.