Preheat the oven to 400℉/204℃ and line a large baking tray with parchment paper. (Or use two if you don't have a very big one.)
Trim the ends of your asparagus, and remove the peels from your carrots. Then quarter the carrots lengthwise if they are medium thickness. If your carrots are very thick, slice them to be approx. the same thinness as your asparagus for even cooking.
Arrange the vegetables on your baking sheet in a single layer. Then drizzle them with lemon juice and sprinkle with the seasoning.
Bake for 20 minutes, and then flip. Then continue baking for another 5-10 minutes or until the desired doneness is reached. (Bake time will vary according to the thickness of your veggies.)
Notes
Slice your carrots very thin (approx. the same thickness as your asparagus) for even cooking.
If your carrots are much thicker than your asparagus, and you're having a hard time cutting them thin enough, give the carrots a 10-15 minute baking head start before adding the asparagus.