Place whole chicken breast side down and cut from neck to bottom and open. Turn back and cut off wings leaving heart shaped chicken breast exposed and lather on marinade.
Place cherry tomatoes and red peppers under the crown of the chicken and put baby potatoes around chicken.
Drizzle olive oil over the potatoes and place around chicken and put dish in oven for 45 minutes.
Once cooked place chicken and potatoes on plate leaving peppers and tomatoes in pan. To make sauce; Melt last stock cube in 200 mls water and add the tomatoes and peppers, and puree until smooth, add tarragon and drizzle sauce over chicken and potatoes