Slice each baguette segment lengthwise. Brush the cut sides with olive oil. Toast in toaster to your preferred darkness, 2 to 4 minutes.

Heat red peppers in a saucepan over medium heat until hot, 2 to 3 minutes.

Spread thick layers of goat cheese onto the cut sides of each baguette piece. Spread red peppers onto 3 of the baguette pieces. Sprinkle balsamic vinegar over the red peppers; top with arugula and basil. Place remaining baguette segments atop the fillings to finish the sandwiches.