Prepare 2 skewers; if using wooden ones, soak in water for 20 minutes to prevent burning.
Skewer hot dog pieces, tomatoes, and pineapple chunks alternately onto the 2 skewers.
Spray grill pan lightly with nonstick spray, and bring to medium-high heat.
Cover and cook kebabs for 4 minutes. Then carefully flip kebabs with barbecue tongs. Re-cover and cook for another 3 to 4 minutes, until tomatoes and pineapple have softened and are slightly blackened.
Once cool enough to handle, pull food off the sticks and eat!