In small bowl, mix together beet juice powder, sugar substitute and salt until combined well. Set aside.
Add oil to large stock pot and add 3 kernels of popcorn, and place lid on pot. Heat oil over medium until the test kernels pop. Then add remainder of popcorn to pot. Once popcorn starts popping, start shaking pot back and forth across burner to prevent burning. Once popping has slowed down and there starts to become a couple seconds between the lingering “pops,” remove from heat.
Immediately, pour half the popcorn in large bowl and sprinkle with approximately half of beet-sugar-salt mixture. Shake around to coat. Working quickly, add remaining half of popcorn and half of beet topping and shake all together until coated as well as possible.