Examples:
Most teams are going for "flavors that they are familiar with".
Most teams are going for "flavors that they know well".
Most teams are "using flavors that they have used many times before".
"Tried and tested" basically means that it is something that you have experienced before. It is not new to you. You know what to expect from that flavor or ingredient.
*I used the American spelling for flavours (flavors).
* The second part of the sentence should say "one team is taking" NOT "one team are taking".