Preheat the oven to 400 degrees F.
Put the ears of corn on a baking sheet and place in the oven for 45 minutes. Remove and let cool. When the corn has cooled, shuck it and stand it on end. Using a sharp knife, run the blade down the cob to cut the kernels off. Rotate the cob and repeat until all the kernels have been cut off.
Combine the jicama, mango, red onion and cilantro in a large mixing bowl. Add the cooled corn, and toss with the vinaigrette. Chill until ready to serve.
In a large bowl combine the lime juice, orange juice, orange zest, sugar and hot sauce. Whisk together and slowly add the olive oil, whisking as you go. Add salt and pepper, to taste, and cilantro and whisk until combined.