Cook pasta with 1 tablespoon kosher salt according
to package directions, omitting additional fat.
Drain in a colander over a bowl, and reserve 1 cup
Combine 1/2 cup reserved hot cooking liquid and
ricotta cheese in a food processor or blender, and
process until well blended.
Combine hot pasta, cheese mixture, spinach, and
remaining ingredients in a large bowl; toss gently
to coat. Add additional cooking liquid to moisten,