Coat a large nonstick skillet with cooking spray; place over high heat until hot. Add beef; cook 5 minutes or until browned. Remove beef; place in a 4 1/2-quart electric slow cooker.
Add water and broth to pan, scraping pan to loosen browned bits; pour over beef in slow cooker. Add potato and next 7 ingredients to slow cooker; stir well. Cover with lid; cook on high-heat setting 6 to 8 hours.
Lightly spoon flour into a dry measuring cup; level with a knife. Combine flour and 1/4 cup water in a bowl; stir well with a whisk until blended. Add flour mixture, thyme, and chives to slow cooker; stir well. Cover and cook on high-heat setting for 20 minutes.