Heat the oil to 350 degrees F in a large saute pan over medium-high heat.
Season the chicken breasts with salt and pepper. Season the flour with some seasoning salt. Lightly dredge both sides of the chicken in the seasoned flour, and then dip in the egg wash, letting the excess drip off, and then dredge in the seasoned flour again. Place the breaded chicken in the saute pan and fry until crisp and golden brown.
In a large bowl, toss together the romaine, tomatoes, and red onions with some of the Sweet Dijon vinaigrette. Slice the fried chicken breasts and arrange on top of the salad.
Sweet Honey Dijon Vinaigrette:
Combine the mustard and vinegar in a small bowl. Whisk the olive oil in a slow, steady stream. Season with sugar, salt, and pepper.