Combine the cilantro, garlic, lime juice, cumin, ½ teaspoon salt and ¼ teaspoon pepper in a blender.
Blend until the cilantro is coarsely chopped. Add the olive oil and blend until smooth.
Taste and adjust the seasonings. Set aside.
For the Salad:
Preheat the oven to 400°F. Brush both sides of the tortillas with olive oil then cut into bite-sized wedges or strips. Arrange the tortilla pieces in a single layer on a small baking sheet and sprinkle lightly with salt.
Bake, stirring once, until golden and toasted, 10 to 12 minutes. Remove from the oven and set aside.
Meanwhile, gently combine the tomatoes, jalapeño and onion in a small bowl and season with ¼ teaspoon salt. Set aside.
Put the corn in a skillet with 1 inch water and cover. Heat over moderately high heat, bring to a boil and cook until corn is just tender, about 5 minutes. Remove from the skillet. When cool enough to handle, cut the kernels from the ears and set aside.
Gently combine the avocado and lime juice in a small bowl.
To assemble the salads, set up 4 clean pint jars on your work surface (or 1 large salad bowl). Divide the romaine between the jars, then top each with an equal layer of chicken, black beans, corn, the tomato mixture, avocado and radishes. Top the salads with a handful of toasted tortillas and 1 tablespoon pumpkin seeds.
Before serving, spoon 2 to 3 tablespoons dressing over each salad and shake or toss to combine. Serve at once.