I have a propane kitchen stove.
The burner grills and those protector catch things that go under them get so dirty and greasy with burnt on food over spill (I live with 2 other people that cook.).
I don't like to use harsh chemicals, some of them make me sick. So I found something by accident that really worked for me. I used Tide laundry soap and hot water and let them soak in a full sink for a while.
I had two Tide tabs I put in, but I have used liquid Tide as well. With minimal scrubbing with a scrubber backed sponge, I got the burnt/caked on food and grease right off. I used the normal cup you would use for a full wash, or both tabs.