[{"_id":1,"basket":[{"key":"A","value":["Bananas"]},{"key":"B","value":["Apples"]}]},{"_id":2,"basket":[{"key":"A","value":["Oranges"]},{"key":"B","value":["Bananas"]}]},{"_id":3,"basket":[{"key":"A","value":["Bananas"]},{"key":"B","value":["Bananas"]}]},{"_id":4,"basket":[{"key":"A","value":["Oranges"]},{"key":"B","value":["Apples"]}]}]

db.collection.find({$expr:{$eq:[{$size:{$filter:{input:"$basket",cond:{$and:[{$in:["Bananas","$$this.value"]},{$in:["$$this.key",["A","B"]]}]}}}},2]}})