On May 7, 1938, there was an 8-cent Relief Meal served at Gold Room at the Congress Hotel.
Chicago Daily Tribune (1923-1963), May 8, 1938
Fifty persons sat down yesterday to the cheapest luncheon ever served in the Gold room of the Congress hotel. Its cost was itemized at 8 cents by the Illinois Workers Alliance of Cook county, which took this way to point to the asserted need for more funds for its members, all on relief.
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This portion was figured from the $28.50 budget of the average relief family of four. It equals 95 cents a day for the whole family. The alliance pointed out, however, that the 8 cents a meal would run less where rent or other necessities must be met from food money.
This experience was replicated at Greater Midwest Foodways program
Midwest Eats! Food of the Great Depression. The menu card with this meal was really 6.99 cents and not 8 cents, in April, 2011, it would have cost $1.79 per person.
Link to breakdown of costs.