Rules
You can't sacrifice more than two Foods to create more than one Giant token.
You choose whether to sacrifice two Foods as Giant Opportunity resolves, not as you cast it.
Food is an artifact type. Even though it appears on some creatures, it's never a creature type.
If an effect refers to a Food, it means any Food artifact, not just a Food artifact token. For example, you can sacrifice Tough Cookie (an Artifact Creature — Food Golem) to activate Maraleaf Rider's ability (an ability with "Sacrifice a Food" in its cost).
Whatever you do, don't eat the delicious cards.
You can't sacrifice a Food to pay multiple costs. For example, you can't sacrifice a Food token to activate its own ability and also to activate Maraleaf Rider's ability.
, 
,Sacrificethis token: You gain 3 life.") 
