With a mortar and pestle, pound a large clove of garlic with a teaspoon of salt to make a paste.
Add the mayonnaise and combine. Transfer to a bowl and refrigerate until needed.
Grill the breasts in a grill pan until cooked through. Remove to a plate to rest.
To toast the bread, brush or spray olive oil onto the cut sides and place in a grill pan. Toast until golden brown with nice grill marks.
Brush some olive oil onto the grill pan and grill the pineapple rings until they are warmed through and take on grill marks.
To assemble the toasts, spread a generous amount of mayonnaise onto a slice of toasted baguette. Layer on the grilled chicken, half a grilled pineapple ring and a strip of roasted red pepper.
Arrange the assembled toasts on a tray and garnish with parsley if desired.
Plan on two or three toasts per serving.