3 1/2c oats
2/3 c sugar
1/4  c flour
1 1/4 sticks butter
1/2 tsp salt
1 tsp vanilla or less (optional I did not use!!)

press firmly in buttered 13 x 9 pan bake at 325 for 30 min

NOTES: I didn’t use vanilla.  Mine took about 45 min until they were lightly browned. CUT while still WARM otherwise they crumble.