Preheat grill to medium high.
Place whole sweet potatoes in a large pot, cover with salted cold water, and bring to a boil. Reduce heat and simmer until fork tender, about 20 minutes, this will depend on the size of your sweet potatoes. Drain potatoes and rinse under cold water until cool enough to handle. With a sharp knife. peel potatoes and cut into 1-inch (2.5 cm) slices.
Meanwhile, cook sausage on pre-heated grill, turning occasionally until cooked through, about 7 to 8 minutes per side. Let cool slightly then slice and place in a large bowl and keep warm.
Whisk together oil, Tex-Mex seasoning, cumin, paprika, salt and pepper, lightly brush on both sides of potato slices. Whisk lime juice with remaining oil to create dressing.
Place potatoes on pre-heated grill and cook for 1-2 minutes per side, or until lightly grilled and golden. Cube potatoes and transfer to bowl with sausage, drizzle with dressing and sprinkle with jalapeño and green onion; toss to combine.
Garnish with chopped cilantro.