The National Paralegal College reports that the test was first introduced during a 1970 U.S. Supreme Court case, Lemon v. Kurtzman.
Preheat oven to 450Â°F. Toss parsnips with oil and salt to taste in a shallow (1-inch-deep) baking pan and roast in middle of oven, turning over halfway through cooking, until golden and tender, 30 to 35 minutes total.oss parsnips with oil and salt to taste in a shallow (1-inch-deep) baking pan and roast in middle of oven, turning over halfway through cooking, until golden and tender, 30 to 35 minutes total.
1 Cook in the oven for 30 minutes at 325 degrees F (165 degrees C). 2  Reduce the heat to 300 degrees F (150 degrees C), and cook for 1 1/2 hours. 3  Remove roast to a platter to rest for 10 to 15 minutes.