With vegetable peeler, remove four 3 inch long strips peel (about 3/4 inch wide each) from 1 orange.
Cut peel lengthwise into very thin slivers.
Squeeze enough juice from 2 oranges to equal 3/4 cup.
Cut peel and white pith from remaining 2 oranges.
Cut each orange in half from stem to blossom end, then cut each half crosswise into 1/4 inch thick slices; set aside.
Rub chicken breasts with salt, pepper, and thyme.
In nonstick 12 inch skillet, heat olive oil over medium high heat until hot.
Add chicken breasts and cook until golden, about 6 minutes, turning once.
Add orange juice, orange peel strips, and chicken broth; heat to boiling.
Reduce heat to low; cover and simmer 20 minutes or until juices run clear when chicken is pierced with tip of knife.
In cup, mix orange marmalade and cornstarch until blended.
Transfer chicken breasts to warm platter; keep warm.
To same skillet, add marmalade mixture; heat to boiling.
Cook, stirring constantly, 1 minute, until sauce thickens slightly.
Stir in orange slices; heat through.
Spoon sauce over chicken breasts on platter.